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h2/src/docsrc/html/changelog.html
浏览文件 @ 68d7ff3f
...@@ -50,8 +50,8 @@ Change Log ...@@ -50,8 +50,8 @@ Change Log
</li><li>Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue </li><li>Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue
sessions are creating large transactions. sessions are creating large transactions.
</li><li>Some small fixes to the GEOMETRY support, patches by Nicolas Fortin. </li><li>Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
</li><li>When the H2 parser fails to parse a SQL statement, throw a more specific exception that </li><li>The BNF tool and the autocomplete feature are exported in OSGi,
contains extra information to make it possible for smart editors to do autocomplete. Patch from Nicolas Fortin. which makes it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
</li><li>Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies. </li><li>Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
</li><li>Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown. </li><li>Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown.
Now they are cleared out at every commit. Now they are cleared out at every commit.
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h2/src/docsrc/html/mvstore.html
浏览文件 @ 68d7ff3f
...@@ -450,13 +450,11 @@ This is work in progress. To try it out, append ...@@ -450,13 +450,11 @@ This is work in progress. To try it out, append
<code>;MV_STORE=TRUE</code> <code>;MV_STORE=TRUE</code>
to the database URL. In general, functionality and performance should be to the database URL. In general, functionality and performance should be
similar than the current default storage engine (the page store). similar than the current default storage engine (the page store).
There are a few features that have not been implemented yet or are not complete: There are a few features that have not been implemented yet or are not complete,
for example there is still a file named <code>.h2.db</code>,
and the <code>.lock.db</code> file is still used to lock a database
(long term, the plan is to no longer use those files).
</p> </p>
<ul><li>There is still a file <code>.h2.db</code>,
and the <code>.lock.db</code> file is still used to lock a database
(long term, the plan is to no longer use those files).
</li><li>The database file(s) sometimes do not shrink as expected.
</li></ul>
<h2 id="differences">Similar Projects and Differences to Other Storage Engines</h2> <h2 id="differences">Similar Projects and Differences to Other Storage Engines</h2>
<p> <p>
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h2/src/docsrc/text/_docs_en.utf8.txt
浏览文件 @ 68d7ff3f
...@@ -1667,567 +1667,609 @@ Change Log ...@@ -1667,567 +1667,609 @@ Change Log
Next Version (unreleased) Next Version (unreleased)
@changelog_1002_li @changelog_1002_li
Improved spatial index and data type. The function "regexp_replace" threw the wrong kind of exception if the replacement string was invalid.
@changelog_1003_li @changelog_1003_li
Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle). A checkpoint is now done every MAX_LOG_SIZE / 2 instead of every MAX_LOG_SIZE, so that the transaction log doesn't grow as large.
@changelog_1004_li @changelog_1004_li
Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases. MVStore table engine: new setting "retention_time" to configure the time to retain old data. The default is 45 seconds.
@changelog_1005_li @changelog_1005_li
Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG The method TableEngine.createTable() now returns a Table object.
@changelog_1006_li @changelog_1006_li
Bug: Changes to the database structure did not result in the Session query cache being invalidated. For read-only databases, for the trace level "debug", the trace info is written to the temp directory.
@changelog_1007_li @changelog_1007_li
Closing the file lock will now wait until the background thread is stopped.
@changelog_1008_li
In version 1.3.172, a performance regression was introduced when fixing the issue 389 (when there is a multi-column primary key, H2 does not seem to always pick the right index). This was related to boosting an index that matches the "order by" column list (the wrong index was used in some cases).
@changelog_1009_li
Improved spatial index and data type.
@changelog_1010_li
Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).
@changelog_1011_li
Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases.
@changelog_1012_li
Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG
@changelog_1013_li
Bug: Changes to the database structure did not result in the Session query cache being invalidated.
@changelog_1014_li
New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis. New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis.
@changelog_1008_h2 @changelog_1015_li
When running the Recover tool on very large (>6G) databases, some statistics were reported with negative numbers.
@changelog_1016_li
Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue sessions are creating large transactions.
@changelog_1017_li
Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
@changelog_1018_li
When the H2 parser fails to parse a SQL statement, throw a more specific exception that contains extra information to make it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
@changelog_1019_li
Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
@changelog_1020_li
Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown. Now they are cleared out at every commit.
@changelog_1021_li
There was a bug where a hash index with more than one column would be silently converted to a regular index. It will now throw an exception.
@changelog_1022_h2
Version 1.3.173 (2013-07-28) Version 1.3.173 (2013-07-28)
@changelog_1009_li @changelog_1023_li
Support empty statements that just contains a comment. Support empty statements that just contains a comment.
@changelog_1010_li @changelog_1024_li
Server mode: if there was an error while reading from a LOB, the session was closed in some cases. Server mode: if there was an error while reading from a LOB, the session was closed in some cases.
@changelog_1011_li @changelog_1025_li
Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData. Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData.
@changelog_1012_li @changelog_1026_li
JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set). JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set).
@changelog_1013_li @changelog_1027_li
For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine. For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine.
@changelog_1014_li @changelog_1028_li
New column "information_schema.tables.row_count_estimate". New column "information_schema.tables.row_count_estimate".
@changelog_1015_li @changelog_1029_li
Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException. Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException.
@changelog_1016_li @changelog_1030_li
The expression trunc(number) threw a NullPointerException. The expression trunc(number) threw a NullPointerException.
@changelog_1017_li @changelog_1031_li
Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2(). Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2().
@changelog_1018_li @changelog_1032_li
Fixed a deadlock related to very large temporary result sets. Fixed a deadlock related to very large temporary result sets.
@changelog_1019_li @changelog_1033_li
Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file. Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file.
@changelog_1020_li @changelog_1034_li
Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski. Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski.
@changelog_1021_li @changelog_1035_li
Issue 476: Broken link in jaqu.html Issue 476: Broken link in jaqu.html
@changelog_1022_li @changelog_1036_li
Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess. Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess.
@changelog_1023_li @changelog_1037_li
Improve error message when check constraint is broken, test case from Gili (cowwoc). Improve error message when check constraint is broken, test case from Gili (cowwoc).
@changelog_1024_li @changelog_1038_li
Improve error message when we have a unique constraint violation, displays the offending key in the error message. Improve error message when we have a unique constraint violation, displays the offending key in the error message.
@changelog_1025_li @changelog_1039_li
Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin. Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin.
@changelog_1026_li @changelog_1040_li
Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin. Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin.
@changelog_1027_li @changelog_1041_li
Issue 473: PgServer missing -key option, patch from Andrew Franklin. Issue 473: PgServer missing -key option, patch from Andrew Franklin.
@changelog_1028_li @changelog_1042_li
Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin. Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin.
@changelog_1029_li @changelog_1043_li
Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin. Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin.
@changelog_1030_li @changelog_1044_li
Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin. Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin.
@changelog_1031_li @changelog_1045_li
Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin. Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin.
@changelog_1032_li @changelog_1046_li
Add syntax for passing additional parameters into custom TableEngine implementations. Add syntax for passing additional parameters into custom TableEngine implementations.
@changelog_1033_li @changelog_1047_li
Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin. Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin.
@changelog_1034_li @changelog_1048_li
Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin. Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin.
@changelog_1035_li @changelog_1049_li
Add support for spatial datatype GEOMETRY. Add support for spatial datatype GEOMETRY.
@changelog_1036_li @changelog_1050_li
Add support for in-memory spatial index. Add support for in-memory spatial index.
@changelog_1037_li @changelog_1051_li
change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates. change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates.
@changelog_1038_li @changelog_1052_li
Fix a NullPointerException when attempting to add foreign key reference to a view. Fix a NullPointerException when attempting to add foreign key reference to a view.
@changelog_1039_li @changelog_1053_li
Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy. Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.
@changelog_1040_li @changelog_1054_li
Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available(). Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available().
@changelog_1041_li @changelog_1055_li
Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory. Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory.
@changelog_1042_li @changelog_1056_li
Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works. Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works.
@changelog_1043_li @changelog_1057_li
Issue 484: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d" Issue 484: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d"
@changelog_1044_li @changelog_1058_li
MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement. MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement.
@changelog_1045_li @changelog_1059_li
Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement. Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
@changelog_1046_li @changelog_1060_li
Issue 487: support the MySQL "SET foreign_key_checks = 0" command Issue 487: support the MySQL "SET foreign_key_checks = 0" command
@changelog_1047_li @changelog_1061_li
Issue 490: support MySQL "USING BTREE" index declaration Issue 490: support MySQL "USING BTREE" index declaration
@changelog_1048_li @changelog_1062_li
Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement. Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
@changelog_1049_li @changelog_1063_li
Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax
@changelog_1050_li @changelog_1064_li
Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel
@changelog_1051_li @changelog_1065_li
Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable. Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.
@changelog_1052_h2 @changelog_1066_h2
Version 1.3.172 (2013-05-25) Version 1.3.172 (2013-05-25)
@changelog_1053_li @changelog_1067_li
Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed. Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed.
@changelog_1054_li @changelog_1068_li
The auto-analyze feature now only reads 1000 rows per table instead of 10000. The auto-analyze feature now only reads 1000 rows per table instead of 10000.
@changelog_1055_li @changelog_1069_li
The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list". The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list".
@changelog_1056_li @changelog_1070_li
Issue 454: Use Charset for type-safety. Issue 454: Use Charset for type-safety.
@changelog_1057_li @changelog_1071_li
Queries with both LIMIT and OFFSET could throw an IllegalArgumentException. Queries with both LIMIT and OFFSET could throw an IllegalArgumentException.
@changelog_1058_li @changelog_1072_li
MVStore: multiple issues were fixed: 460, 461, 462, 464, 466. MVStore: multiple issues were fixed: 460, 461, 462, 464, 466.
@changelog_1059_li @changelog_1073_li
MVStore: larger stores (multiple GB) are now much faster. MVStore: larger stores (multiple GB) are now much faster.
@changelog_1060_li @changelog_1074_li
When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool). When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool).
@changelog_1061_li @changelog_1075_li
Support TRUNC(timestamp) for improved Oracle compatibility. Support TRUNC(timestamp) for improved Oracle compatibility.
@changelog_1062_li @changelog_1076_li
Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long. Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long.
@changelog_1063_li @changelog_1077_li
Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode. Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode.
@changelog_1064_li @changelog_1078_li
Issue 453: ABBA race conditions in TABLE LINK connection sharing. Issue 453: ABBA race conditions in TABLE LINK connection sharing.
@changelog_1065_li @changelog_1079_li
Issue 449: Postgres Serial data type should not automatically be marked as primary key Issue 449: Postgres Serial data type should not automatically be marked as primary key
@changelog_1066_li @changelog_1080_li
Issue 406: Support "select h2version()" Issue 406: Support "select h2version()"
@changelog_1067_li @changelog_1081_li
Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index
@changelog_1068_li @changelog_1082_li
Issue 305: Implement SELECT ... FOR FETCH ONLY Issue 305: Implement SELECT ... FOR FETCH ONLY
@changelog_1069_li @changelog_1083_li
Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions
@changelog_1070_li @changelog_1084_li
Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function. Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function.
@changelog_1071_li @changelog_1085_li
Issue 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)" Issue 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)"
@changelog_1072_li @changelog_1086_li
Fix bug in Optimizing SELECT * FROM A WHERE X=1 OR X=2 OR X=3 into SELECT * FROM A WHERE X IN (1,2,3) Fix bug in Optimizing SELECT * FROM A WHERE X=1 OR X=2 OR X=3 into SELECT * FROM A WHERE X IN (1,2,3)
@changelog_1073_li @changelog_1087_li
Issue 442: Groovy patch for SourceCompiler (function ALIAS) Issue 442: Groovy patch for SourceCompiler (function ALIAS)
@changelog_1074_li @changelog_1088_li
Issue 459: Improve LOB documentation Issue 459: Improve LOB documentation
@changelog_1075_h2 @changelog_1089_h2
Version 1.3.171 (2013-03-17) Version 1.3.171 (2013-03-17)
@changelog_1076_li @changelog_1090_li
Security: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers". Security: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers".
@changelog_1077_li @changelog_1091_li
H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout". H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout".
@changelog_1078_li @changelog_1092_li
Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table. Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table.
@changelog_1079_li @changelog_1093_li
Issue 249: Improved compatibility with MySQL in the MySQL mode: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode. Issue 249: Improved compatibility with MySQL in the MySQL mode: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode.
@changelog_1080_li @changelog_1094_li
Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument. Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument.
@changelog_1081_li @changelog_1095_li
There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database. There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database.
@changelog_1082_li @changelog_1096_li
The SQL script generated by the "script" command contained inconsistent newlines on Windows. The SQL script generated by the "script" command contained inconsistent newlines on Windows.
@changelog_1083_li @changelog_1097_li
When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made. When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made.
@changelog_1084_li @changelog_1098_li
Optimize IN(...) queries: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed. Optimize IN(...) queries: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed.
@changelog_1085_li @changelog_1099_li
Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed. Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed.
@changelog_1086_li @changelog_1100_li
Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23:00:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem! Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23:00:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem!
@changelog_1087_li @changelog_1101_li
New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db". New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db".
@changelog_1088_li @changelog_1102_li
New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine. New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine.
@changelog_1089_li @changelog_1103_li
MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128. MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128.
@changelog_1090_li @changelog_1104_li
MVStore: improved API thanks to Simo Tripodi. MVStore: improved API thanks to Simo Tripodi.
@changelog_1091_li @changelog_1105_li
MVStore: maps can now be renamed. MVStore: maps can now be renamed.
@changelog_1092_li @changelog_1106_li
MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations. MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations.
@changelog_1093_li @changelog_1107_li
MVStore: a map implementation that supports concurrent operations. MVStore: a map implementation that supports concurrent operations.
@changelog_1094_li @changelog_1108_li
MVStore: unified exception handling; the version is included in the messages. MVStore: unified exception handling; the version is included in the messages.
@changelog_1095_li @changelog_1109_li
MVStore: old data is now retained for 45 seconds by default. MVStore: old data is now retained for 45 seconds by default.
@changelog_1096_li @changelog_1110_li
MVStore: compress is now disabled by default, and can be enabled on request. MVStore: compress is now disabled by default, and can be enabled on request.
@changelog_1097_li @changelog_1111_li
Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401. Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401.
@changelog_1098_li @changelog_1112_li
Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365. Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365.
@changelog_1099_li @changelog_1113_li
Add a DISK_SPACE_USED system function. Fixes issue 270. Add a DISK_SPACE_USED system function. Fixes issue 270.
@changelog_1100_li @changelog_1114_li
Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder. Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder.
@changelog_1101_li @changelog_1115_li
Supporting dropping an index for Lucene full-text indexes. Supporting dropping an index for Lucene full-text indexes.
@changelog_1102_li @changelog_1116_li
Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin). Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin).
@changelog_1103_li @changelog_1117_li
Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman. Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman.
@changelog_1104_li @changelog_1118_li
Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169. Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169.
@changelog_1105_li @changelog_1119_li
MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela. MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela.
@changelog_1106_li @changelog_1120_li
Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS. Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS.
@changelog_1107_li @changelog_1121_li
Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW. Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW.
@changelog_1108_li @changelog_1122_li
Issue 439: Utils.sortTopN does not handle single-element arrays. Issue 439: Utils.sortTopN does not handle single-element arrays.
@changelog_1109_h2 @changelog_1123_h2
Version 1.3.170 (2012-11-30) Version 1.3.170 (2012-11-30)
@changelog_1110_li @changelog_1124_li
Issue 407: The TriggerAdapter didn't work with CLOB and BLOB columns. Issue 407: The TriggerAdapter didn't work with CLOB and BLOB columns.
@changelog_1111_li @changelog_1125_li
PostgreSQL compatibility: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT. PostgreSQL compatibility: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT.
@changelog_1112_li @changelog_1126_li
Issue 417: H2 Console: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened. Issue 417: H2 Console: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened.
@changelog_1113_li @changelog_1127_li
Issue 412: Running the Server tool with just the option "-browser" will now log a warning. Issue 412: Running the Server tool with just the option "-browser" will now log a warning.
@changelog_1114_li @changelog_1128_li
Issue 411: CloseWatcher registration was not concurrency-safe. Issue 411: CloseWatcher registration was not concurrency-safe.
@changelog_1115_li @changelog_1129_li
MySQL compatibility: support for CONCAT_WS. Thanks a lot to litailang for the patch! MySQL compatibility: support for CONCAT_WS. Thanks a lot to litailang for the patch!
@changelog_1116_li @changelog_1130_li
PostgreSQL compatibility: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch! PostgreSQL compatibility: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch!
@changelog_1117_li @changelog_1131_li
Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints. Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints.
@changelog_1118_li @changelog_1132_li
Support BOM at the beginning of files for the RUNSCRIPT command Support BOM at the beginning of files for the RUNSCRIPT command
@changelog_1119_li @changelog_1133_li
Fix in calling SET @X = IDENTITY() where it would return NULL incorrectly Fix in calling SET @X = IDENTITY() where it would return NULL incorrectly
@changelog_1120_li @changelog_1134_li
Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread. Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread.
@changelog_1121_li @changelog_1135_li
Optimize IN(...) queries where the values are constant and of the same type. Optimize IN(...) queries where the values are constant and of the same type.
@changelog_1122_li @changelog_1136_li
Restore tool: the parameter "quiet" was not used and is now removed. Restore tool: the parameter "quiet" was not used and is now removed.
@changelog_1123_li @changelog_1137_li
Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych. Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych.
@changelog_1124_li @changelog_1138_li
Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch! Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch!
@changelog_1125_h2 @changelog_1139_h2
Version 1.3.169 (2012-09-09) Version 1.3.169 (2012-09-09)
@changelog_1126_li @changelog_1140_li
The default jar file is now compiled for Java 6. The default jar file is now compiled for Java 6.
@changelog_1127_li @changelog_1141_li
The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual. The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual.
@changelog_1128_li @changelog_1142_li
A part of the documentation and the H2 Console has been changed to support the Apple retina display. A part of the documentation and the H2 Console has been changed to support the Apple retina display.
@changelog_1129_li @changelog_1143_li
The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode. The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode.
@changelog_1130_li @changelog_1144_li
Statement.getQueryTimeout(): only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot. Statement.getQueryTimeout(): only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot.
@changelog_1131_li @changelog_1145_li
Issue 416: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file. Issue 416: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file.
@changelog_1132_li @changelog_1146_li
Issue 414: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice). Issue 414: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice).
@changelog_1133_li @changelog_1147_li
The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API. The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API.
@changelog_1134_li @changelog_1148_li
Added compatibility for "SET NAMES" query in MySQL compatibility mode. Added compatibility for "SET NAMES" query in MySQL compatibility mode.
@changelog_1135_h2 @changelog_1149_h2
Version 1.3.168 (2012-07-13) Version 1.3.168 (2012-07-13)
@changelog_1136_li @changelog_1150_li
The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log. The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log.
@changelog_1137_li @changelog_1151_li
New system property "h2.serializeJavaObject" (default: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used. New system property "h2.serializeJavaObject" (default: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used.
@changelog_1138_li @changelog_1152_li
Dylan has translated the H2 Console tool to Korean. Thanks a lot! Dylan has translated the H2 Console tool to Korean. Thanks a lot!
@changelog_1139_li @changelog_1153_li
Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database. Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database.
@changelog_1140_li @changelog_1154_li
MVCC: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch! MVCC: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch!
@changelog_1141_li @changelog_1155_li
Fulltext search: in-memory Lucene indexes are now supported. Fulltext search: in-memory Lucene indexes are now supported.
@changelog_1142_li @changelog_1156_li
Fulltext search: UUID primary keys are now supported. Fulltext search: UUID primary keys are now supported.
@changelog_1143_li @changelog_1157_li
Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool. Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool.
@changelog_1144_li @changelog_1158_li
H2 Console: support the Midori browser (for Debian / Raspberry Pi) H2 Console: support the Midori browser (for Debian / Raspberry Pi)
@changelog_1145_li @changelog_1159_li
When opening a remote session, don't open a temporary file if the trace level is set to zero When opening a remote session, don't open a temporary file if the trace level is set to zero
@changelog_1146_li @changelog_1160_li
Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set. Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set.
@changelog_1147_li @changelog_1161_li
H2 Console: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents. H2 Console: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents.
@changelog_1148_h2 @changelog_1162_h2
Version 1.3.167 (2012-05-23) Version 1.3.167 (2012-05-23)
@changelog_1149_li @changelog_1163_li
H2 Console: when editing a row, an empty varchar column was replaced with a single space. H2 Console: when editing a row, an empty varchar column was replaced with a single space.
@changelog_1150_li @changelog_1164_li
Lukas Eder has updated the jOOQ documentation. Lukas Eder has updated the jOOQ documentation.
@changelog_1151_li @changelog_1165_li
Some nested joins could not be executed, for example: select * from (select * from (select * from a) a right join b b) c; Some nested joins could not be executed, for example: select * from (select * from (select * from a) a right join b b) c;
@changelog_1152_li @changelog_1166_li
MS SQL Server compatibility: ISNULL is now an alias for IFNULL. MS SQL Server compatibility: ISNULL is now an alias for IFNULL.
@changelog_1153_li @changelog_1167_li
Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot! Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot!
@changelog_1154_li @changelog_1168_li
Server mode: the number of CLOB / BLOB values that were cached on the server is now the maximum of: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS. Server mode: the number of CLOB / BLOB values that were cached on the server is now the maximum of: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS.
@changelog_1155_li @changelog_1169_li
In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2. In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2.
@changelog_1156_li @changelog_1170_li
The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required. The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required.
@changelog_1157_li @changelog_1171_li
Then reading from a resource using the prefix "classpath:", the ContextClassLoader is now used if the resource can't be read otherwise. Then reading from a resource using the prefix "classpath:", the ContextClassLoader is now used if the resource can't be read otherwise.
@changelog_1158_li @changelog_1172_li
DatabaseEventListener now calls setProgress whenever a statement starts and ends. DatabaseEventListener now calls setProgress whenever a statement starts and ends.
@changelog_1159_li @changelog_1173_li
DatabaseEventListener now calls setProgress periodically while a statement is running. DatabaseEventListener now calls setProgress periodically while a statement is running.
@changelog_1160_li @changelog_1174_li
The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME. The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME.
@changelog_1161_li @changelog_1175_li
Issue 378: when using views, the wrong values were bound to a parameter in some cases. Issue 378: when using views, the wrong values were bound to a parameter in some cases.
@changelog_1162_li @changelog_1176_li
Terrence Huang has translated the error messages to Chinese. Thanks a lot! Terrence Huang has translated the error messages to Chinese. Thanks a lot!
@changelog_1163_li @changelog_1177_li
TRUNC was added as an alias for TRUNCATE. TRUNC was added as an alias for TRUNCATE.
@changelog_1164_li @changelog_1178_li
Small optimisation for accessing result values by column name. Small optimisation for accessing result values by column name.
@changelog_1165_li @changelog_1179_li
Fix for bug in Statement.getMoreResults(int) Fix for bug in Statement.getMoreResults(int)
@changelog_1166_li @changelog_1180_li
The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch! The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch!
@changelog_1167_h2 @changelog_1181_h2
Version 1.3.166 (2012-04-08) Version 1.3.166 (2012-04-08)
@changelog_1168_li @changelog_1182_li
Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space. Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space.
@changelog_1169_li @changelog_1183_li
Server mode: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown. Server mode: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown.
@changelog_1170_li @changelog_1184_li
ConvertTraceFile: the time in the trace file is now parsed as a long. ConvertTraceFile: the time in the trace file is now parsed as a long.
@changelog_1171_li @changelog_1185_li
Invalid connection settings are now detected. Invalid connection settings are now detected.
@changelog_1172_li @changelog_1186_li
Issue 387: WHERE condition getting pushed into sub-query with LIMIT. Issue 387: WHERE condition getting pushed into sub-query with LIMIT.
@changelog_1173_h2 @changelog_1187_h2
Version 1.3.165 (2012-03-18) Version 1.3.165 (2012-03-18)
@changelog_1174_li @changelog_1188_li
Better string representation for decimal values (for example 0.00000000 instead of 0E-26). Better string representation for decimal values (for example 0.00000000 instead of 0E-26).
@changelog_1175_li @changelog_1189_li
Prepared statements could only be re-used if the same data types were used the second time they were executed. Prepared statements could only be re-used if the same data types were used the second time they were executed.
@changelog_1176_li @changelog_1190_li
In error messages about referential constraint violation, the values are now included. In error messages about referential constraint violation, the values are now included.
@changelog_1177_li @changelog_1191_li
SCRIPT and RUNSCRIPT: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement. SCRIPT and RUNSCRIPT: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement.
@changelog_1178_li @changelog_1192_li
MySQL compatibility: SUBSTR with a negative start index now works like MySQL. MySQL compatibility: SUBSTR with a negative start index now works like MySQL.
@changelog_1179_li @changelog_1193_li
When enabling autocommit, the transaction is now committed (as required by the JDBC API). When enabling autocommit, the transaction is now committed (as required by the JDBC API).
@changelog_1180_li @changelog_1194_li
The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch! The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch!
@changelog_1181_li @changelog_1195_li
If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB). If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB).
@changelog_1182_li @changelog_1196_li
ALTER TABLE ADD can now add more than one column at a time. ALTER TABLE ADD can now add more than one column at a time.
@changelog_1183_li @changelog_1197_li
Issue 380: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on. Issue 380: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on.
@changelog_1184_li @changelog_1198_li
Issue 384: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression. Issue 384: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression.
@changelog_1185_li @changelog_1199_li
Issue 362: support LIMIT in UPDATE statements. Issue 362: support LIMIT in UPDATE statements.
@changelog_1186_li @changelog_1200_li
Browser: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before). Browser: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before).
@changelog_1187_li @changelog_1201_li
CSV tool: new feature to disable writing the column header (option writeColumnHeader). CSV tool: new feature to disable writing the column header (option writeColumnHeader).
@changelog_1188_li @changelog_1202_li
CSV tool: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames). CSV tool: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames).
@changelog_1189_li @changelog_1203_li
PostgreSQL compatibility: LOG(x) is base 10 in the PostgreSQL mode. PostgreSQL compatibility: LOG(x) is base 10 in the PostgreSQL mode.
@cheatSheet_1000_h1 @cheatSheet_1000_h1
...@@ -7019,7 +7061,7 @@ Transactions ...@@ -7019,7 +7061,7 @@ Transactions
In-Memory Performance and Usage In-Memory Performance and Usage
@mvstore_1060_p @mvstore_1060_p
Performance of in-memory operations is comparable with <code>java.util.TreeMap</code> (many operations are actually faster), but usually slower than <code>java.util.HashMap</code>. Performance of in-memory operations is comparable with <code>java.util.TreeMap</code>, but usually slower than <code>java.util.HashMap</code>.
@mvstore_1061_p @mvstore_1061_p
The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory. The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory.
...@@ -8663,7 +8705,7 @@ Berne ...@@ -8663,7 +8705,7 @@ Berne
123 012 345 123 012 345
@performance_1485_p @performance_1485_p
Access by row id is fast because the data is sorted by this key. If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>: Access by row id is fast because the data is sorted by this key. Please note the row id is not available until after the row was added (that means, it can not be used in computed columns or constraints). If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>:
@performance_1486_h3 @performance_1486_h3
Indexes Indexes
......
h2/src/docsrc/text/_docs_ja.utf8.txt
浏览文件 @ 68d7ff3f
...@@ -1667,567 +1667,609 @@ Centralリ�?ジトリ�?�利用 ...@@ -1667,567 +1667,609 @@ Centralリ�?ジトリ�?�利用
#Next Version (unreleased) #Next Version (unreleased)
@changelog_1002_li @changelog_1002_li
#Improved spatial index and data type. #The function "regexp_replace" threw the wrong kind of exception if the replacement string was invalid.
@changelog_1003_li @changelog_1003_li
#Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle). #A checkpoint is now done every MAX_LOG_SIZE / 2 instead of every MAX_LOG_SIZE, so that the transaction log doesn't grow as large.
@changelog_1004_li @changelog_1004_li
#Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases. #MVStore table engine: new setting "retention_time" to configure the time to retain old data. The default is 45 seconds.
@changelog_1005_li @changelog_1005_li
#Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG #The method TableEngine.createTable() now returns a Table object.
@changelog_1006_li @changelog_1006_li
#Bug: Changes to the database structure did not result in the Session query cache being invalidated. #For read-only databases, for the trace level "debug", the trace info is written to the temp directory.
@changelog_1007_li @changelog_1007_li
#Closing the file lock will now wait until the background thread is stopped.
@changelog_1008_li
#In version 1.3.172, a performance regression was introduced when fixing the issue 389 (when there is a multi-column primary key, H2 does not seem to always pick the right index). This was related to boosting an index that matches the "order by" column list (the wrong index was used in some cases).
@changelog_1009_li
#Improved spatial index and data type.
@changelog_1010_li
#Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).
@changelog_1011_li
#Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases.
@changelog_1012_li
#Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG
@changelog_1013_li
#Bug: Changes to the database structure did not result in the Session query cache being invalidated.
@changelog_1014_li
#New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis. #New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis.
@changelog_1008_h2 @changelog_1015_li
#When running the Recover tool on very large (>6G) databases, some statistics were reported with negative numbers.
@changelog_1016_li
#Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue sessions are creating large transactions.
@changelog_1017_li
#Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
@changelog_1018_li
#When the H2 parser fails to parse a SQL statement, throw a more specific exception that contains extra information to make it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
@changelog_1019_li
#Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
@changelog_1020_li
#Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown. Now they are cleared out at every commit.
@changelog_1021_li
#There was a bug where a hash index with more than one column would be silently converted to a regular index. It will now throw an exception.
@changelog_1022_h2
#Version 1.3.173 (2013-07-28) #Version 1.3.173 (2013-07-28)
@changelog_1009_li @changelog_1023_li
#Support empty statements that just contains a comment. #Support empty statements that just contains a comment.
@changelog_1010_li @changelog_1024_li
#Server mode: if there was an error while reading from a LOB, the session was closed in some cases. #Server mode: if there was an error while reading from a LOB, the session was closed in some cases.
@changelog_1011_li @changelog_1025_li
#Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData. #Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData.
@changelog_1012_li @changelog_1026_li
#JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set). #JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set).
@changelog_1013_li @changelog_1027_li
#For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine. #For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine.
@changelog_1014_li @changelog_1028_li
#New column "information_schema.tables.row_count_estimate". #New column "information_schema.tables.row_count_estimate".
@changelog_1015_li @changelog_1029_li
#Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException. #Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException.
@changelog_1016_li @changelog_1030_li
#The expression trunc(number) threw a NullPointerException. #The expression trunc(number) threw a NullPointerException.
@changelog_1017_li @changelog_1031_li
#Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2(). #Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2().
@changelog_1018_li @changelog_1032_li
#Fixed a deadlock related to very large temporary result sets. #Fixed a deadlock related to very large temporary result sets.
@changelog_1019_li @changelog_1033_li
#Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file. #Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file.
@changelog_1020_li @changelog_1034_li
#Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski. #Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski.
@changelog_1021_li @changelog_1035_li
#Issue 476: Broken link in jaqu.html #Issue 476: Broken link in jaqu.html
@changelog_1022_li @changelog_1036_li
#Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess. #Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess.
@changelog_1023_li @changelog_1037_li
#Improve error message when check constraint is broken, test case from Gili (cowwoc). #Improve error message when check constraint is broken, test case from Gili (cowwoc).
@changelog_1024_li @changelog_1038_li
#Improve error message when we have a unique constraint violation, displays the offending key in the error message. #Improve error message when we have a unique constraint violation, displays the offending key in the error message.
@changelog_1025_li @changelog_1039_li
#Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin. #Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin.
@changelog_1026_li @changelog_1040_li
#Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin. #Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin.
@changelog_1027_li @changelog_1041_li
#Issue 473: PgServer missing -key option, patch from Andrew Franklin. #Issue 473: PgServer missing -key option, patch from Andrew Franklin.
@changelog_1028_li @changelog_1042_li
#Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin. #Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin.
@changelog_1029_li @changelog_1043_li
#Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin. #Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin.
@changelog_1030_li @changelog_1044_li
#Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin. #Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin.
@changelog_1031_li @changelog_1045_li
#Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin. #Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin.
@changelog_1032_li @changelog_1046_li
#Add syntax for passing additional parameters into custom TableEngine implementations. #Add syntax for passing additional parameters into custom TableEngine implementations.
@changelog_1033_li @changelog_1047_li
#Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin. #Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin.
@changelog_1034_li @changelog_1048_li
#Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin. #Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin.
@changelog_1035_li @changelog_1049_li
#Add support for spatial datatype GEOMETRY. #Add support for spatial datatype GEOMETRY.
@changelog_1036_li @changelog_1050_li
#Add support for in-memory spatial index. #Add support for in-memory spatial index.
@changelog_1037_li @changelog_1051_li
#change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates. #change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates.
@changelog_1038_li @changelog_1052_li
#Fix a NullPointerException when attempting to add foreign key reference to a view. #Fix a NullPointerException when attempting to add foreign key reference to a view.
@changelog_1039_li @changelog_1053_li
#Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy. #Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.
@changelog_1040_li @changelog_1054_li
#Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available(). #Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available().
@changelog_1041_li @changelog_1055_li
#Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory. #Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory.
@changelog_1042_li @changelog_1056_li
#Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works. #Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works.
@changelog_1043_li @changelog_1057_li
#Issue 484: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d" #Issue 484: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d"
@changelog_1044_li @changelog_1058_li
#MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement. #MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement.
@changelog_1045_li @changelog_1059_li
#Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement. #Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
@changelog_1046_li @changelog_1060_li
#Issue 487: support the MySQL "SET foreign_key_checks = 0" command #Issue 487: support the MySQL "SET foreign_key_checks = 0" command
@changelog_1047_li @changelog_1061_li
#Issue 490: support MySQL "USING BTREE" index declaration #Issue 490: support MySQL "USING BTREE" index declaration
@changelog_1048_li @changelog_1062_li
#Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement. #Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
@changelog_1049_li @changelog_1063_li
#Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax #Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax
@changelog_1050_li @changelog_1064_li
#Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel #Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel
@changelog_1051_li @changelog_1065_li
#Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable. #Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.
@changelog_1052_h2 @changelog_1066_h2
#Version 1.3.172 (2013-05-25) #Version 1.3.172 (2013-05-25)
@changelog_1053_li @changelog_1067_li
#Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed. #Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed.
@changelog_1054_li @changelog_1068_li
#The auto-analyze feature now only reads 1000 rows per table instead of 10000. #The auto-analyze feature now only reads 1000 rows per table instead of 10000.
@changelog_1055_li @changelog_1069_li
#The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list". #The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list".
@changelog_1056_li @changelog_1070_li
#Issue 454: Use Charset for type-safety. #Issue 454: Use Charset for type-safety.
@changelog_1057_li @changelog_1071_li
#Queries with both LIMIT and OFFSET could throw an IllegalArgumentException. #Queries with both LIMIT and OFFSET could throw an IllegalArgumentException.
@changelog_1058_li @changelog_1072_li
#MVStore: multiple issues were fixed: 460, 461, 462, 464, 466. #MVStore: multiple issues were fixed: 460, 461, 462, 464, 466.
@changelog_1059_li @changelog_1073_li
#MVStore: larger stores (multiple GB) are now much faster. #MVStore: larger stores (multiple GB) are now much faster.
@changelog_1060_li @changelog_1074_li
#When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool). #When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool).
@changelog_1061_li @changelog_1075_li
#Support TRUNC(timestamp) for improved Oracle compatibility. #Support TRUNC(timestamp) for improved Oracle compatibility.
@changelog_1062_li @changelog_1076_li
#Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long. #Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long.
@changelog_1063_li @changelog_1077_li
#Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode. #Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode.
@changelog_1064_li @changelog_1078_li
#Issue 453: ABBA race conditions in TABLE LINK connection sharing. #Issue 453: ABBA race conditions in TABLE LINK connection sharing.
@changelog_1065_li @changelog_1079_li
#Issue 449: Postgres Serial data type should not automatically be marked as primary key #Issue 449: Postgres Serial data type should not automatically be marked as primary key
@changelog_1066_li @changelog_1080_li
#Issue 406: Support "select h2version()" #Issue 406: Support "select h2version()"
@changelog_1067_li @changelog_1081_li
#Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index #Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index
@changelog_1068_li @changelog_1082_li
#Issue 305: Implement SELECT ... FOR FETCH ONLY #Issue 305: Implement SELECT ... FOR FETCH ONLY
@changelog_1069_li @changelog_1083_li
#Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions #Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions
@changelog_1070_li @changelog_1084_li
#Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function. #Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function.
@changelog_1071_li @changelog_1085_li
#Issue 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)" #Issue 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)"
@changelog_1072_li @changelog_1086_li
#Fix bug in Optimizing SELECT * FROM A WHERE X=1 OR X=2 OR X=3 into SELECT * FROM A WHERE X IN (1,2,3) #Fix bug in Optimizing SELECT * FROM A WHERE X=1 OR X=2 OR X=3 into SELECT * FROM A WHERE X IN (1,2,3)
@changelog_1073_li @changelog_1087_li
#Issue 442: Groovy patch for SourceCompiler (function ALIAS) #Issue 442: Groovy patch for SourceCompiler (function ALIAS)
@changelog_1074_li @changelog_1088_li
#Issue 459: Improve LOB documentation #Issue 459: Improve LOB documentation
@changelog_1075_h2 @changelog_1089_h2
#Version 1.3.171 (2013-03-17) #Version 1.3.171 (2013-03-17)
@changelog_1076_li @changelog_1090_li
#Security: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers". #Security: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers".
@changelog_1077_li @changelog_1091_li
#H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout". #H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout".
@changelog_1078_li @changelog_1092_li
#Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table. #Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table.
@changelog_1079_li @changelog_1093_li
#Issue 249: Improved compatibility with MySQL in the MySQL mode: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode. #Issue 249: Improved compatibility with MySQL in the MySQL mode: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode.
@changelog_1080_li @changelog_1094_li
#Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument. #Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument.
@changelog_1081_li @changelog_1095_li
#There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database. #There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database.
@changelog_1082_li @changelog_1096_li
#The SQL script generated by the "script" command contained inconsistent newlines on Windows. #The SQL script generated by the "script" command contained inconsistent newlines on Windows.
@changelog_1083_li @changelog_1097_li
#When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made. #When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made.
@changelog_1084_li @changelog_1098_li
#Optimize IN(...) queries: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed. #Optimize IN(...) queries: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed.
@changelog_1085_li @changelog_1099_li
#Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed. #Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed.
@changelog_1086_li @changelog_1100_li
#Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23:00:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem! #Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23:00:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem!
@changelog_1087_li @changelog_1101_li
#New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db". #New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db".
@changelog_1088_li @changelog_1102_li
#New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine. #New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine.
@changelog_1089_li @changelog_1103_li
#MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128. #MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128.
@changelog_1090_li @changelog_1104_li
#MVStore: improved API thanks to Simo Tripodi. #MVStore: improved API thanks to Simo Tripodi.
@changelog_1091_li @changelog_1105_li
#MVStore: maps can now be renamed. #MVStore: maps can now be renamed.
@changelog_1092_li @changelog_1106_li
#MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations. #MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations.
@changelog_1093_li @changelog_1107_li
#MVStore: a map implementation that supports concurrent operations. #MVStore: a map implementation that supports concurrent operations.
@changelog_1094_li @changelog_1108_li
#MVStore: unified exception handling; the version is included in the messages. #MVStore: unified exception handling; the version is included in the messages.
@changelog_1095_li @changelog_1109_li
#MVStore: old data is now retained for 45 seconds by default. #MVStore: old data is now retained for 45 seconds by default.
@changelog_1096_li @changelog_1110_li
#MVStore: compress is now disabled by default, and can be enabled on request. #MVStore: compress is now disabled by default, and can be enabled on request.
@changelog_1097_li @changelog_1111_li
#Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401. #Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401.
@changelog_1098_li @changelog_1112_li
#Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365. #Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365.
@changelog_1099_li @changelog_1113_li
#Add a DISK_SPACE_USED system function. Fixes issue 270. #Add a DISK_SPACE_USED system function. Fixes issue 270.
@changelog_1100_li @changelog_1114_li
#Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder. #Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder.
@changelog_1101_li @changelog_1115_li
#Supporting dropping an index for Lucene full-text indexes. #Supporting dropping an index for Lucene full-text indexes.
@changelog_1102_li @changelog_1116_li
#Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin). #Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin).
@changelog_1103_li @changelog_1117_li
#Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman. #Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman.
@changelog_1104_li @changelog_1118_li
#Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169. #Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169.
@changelog_1105_li @changelog_1119_li
#MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela. #MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela.
@changelog_1106_li @changelog_1120_li
#Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS. #Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS.
@changelog_1107_li @changelog_1121_li
#Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW. #Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW.
@changelog_1108_li @changelog_1122_li
#Issue 439: Utils.sortTopN does not handle single-element arrays. #Issue 439: Utils.sortTopN does not handle single-element arrays.
@changelog_1109_h2 @changelog_1123_h2
#Version 1.3.170 (2012-11-30) #Version 1.3.170 (2012-11-30)
@changelog_1110_li @changelog_1124_li
#Issue 407: The TriggerAdapter didn't work with CLOB and BLOB columns. #Issue 407: The TriggerAdapter didn't work with CLOB and BLOB columns.
@changelog_1111_li @changelog_1125_li
#PostgreSQL compatibility: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT. #PostgreSQL compatibility: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT.
@changelog_1112_li @changelog_1126_li
#Issue 417: H2 Console: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened. #Issue 417: H2 Console: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened.
@changelog_1113_li @changelog_1127_li
#Issue 412: Running the Server tool with just the option "-browser" will now log a warning. #Issue 412: Running the Server tool with just the option "-browser" will now log a warning.
@changelog_1114_li @changelog_1128_li
#Issue 411: CloseWatcher registration was not concurrency-safe. #Issue 411: CloseWatcher registration was not concurrency-safe.
@changelog_1115_li @changelog_1129_li
#MySQL compatibility: support for CONCAT_WS. Thanks a lot to litailang for the patch! #MySQL compatibility: support for CONCAT_WS. Thanks a lot to litailang for the patch!
@changelog_1116_li @changelog_1130_li
#PostgreSQL compatibility: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch! #PostgreSQL compatibility: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch!
@changelog_1117_li @changelog_1131_li
#Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints. #Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints.
@changelog_1118_li @changelog_1132_li
#Support BOM at the beginning of files for the RUNSCRIPT command #Support BOM at the beginning of files for the RUNSCRIPT command
@changelog_1119_li @changelog_1133_li
#Fix in calling SET @X = IDENTITY() where it would return NULL incorrectly #Fix in calling SET @X = IDENTITY() where it would return NULL incorrectly
@changelog_1120_li @changelog_1134_li
#Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread. #Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread.
@changelog_1121_li @changelog_1135_li
#Optimize IN(...) queries where the values are constant and of the same type. #Optimize IN(...) queries where the values are constant and of the same type.
@changelog_1122_li @changelog_1136_li
#Restore tool: the parameter "quiet" was not used and is now removed. #Restore tool: the parameter "quiet" was not used and is now removed.
@changelog_1123_li @changelog_1137_li
#Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych. #Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych.
@changelog_1124_li @changelog_1138_li
#Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch! #Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch!
@changelog_1125_h2 @changelog_1139_h2
#Version 1.3.169 (2012-09-09) #Version 1.3.169 (2012-09-09)
@changelog_1126_li @changelog_1140_li
#The default jar file is now compiled for Java 6. #The default jar file is now compiled for Java 6.
@changelog_1127_li @changelog_1141_li
#The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual. #The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual.
@changelog_1128_li @changelog_1142_li
#A part of the documentation and the H2 Console has been changed to support the Apple retina display. #A part of the documentation and the H2 Console has been changed to support the Apple retina display.
@changelog_1129_li @changelog_1143_li
#The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode. #The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode.
@changelog_1130_li @changelog_1144_li
#Statement.getQueryTimeout(): only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot. #Statement.getQueryTimeout(): only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot.
@changelog_1131_li @changelog_1145_li
#Issue 416: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file. #Issue 416: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file.
@changelog_1132_li @changelog_1146_li
#Issue 414: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice). #Issue 414: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice).
@changelog_1133_li @changelog_1147_li
#The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API. #The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API.
@changelog_1134_li @changelog_1148_li
#Added compatibility for "SET NAMES" query in MySQL compatibility mode. #Added compatibility for "SET NAMES" query in MySQL compatibility mode.
@changelog_1135_h2 @changelog_1149_h2
#Version 1.3.168 (2012-07-13) #Version 1.3.168 (2012-07-13)
@changelog_1136_li @changelog_1150_li
#The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log. #The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log.
@changelog_1137_li @changelog_1151_li
#New system property "h2.serializeJavaObject" (default: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used. #New system property "h2.serializeJavaObject" (default: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used.
@changelog_1138_li @changelog_1152_li
#Dylan has translated the H2 Console tool to Korean. Thanks a lot! #Dylan has translated the H2 Console tool to Korean. Thanks a lot!
@changelog_1139_li @changelog_1153_li
#Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database. #Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database.
@changelog_1140_li @changelog_1154_li
#MVCC: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch! #MVCC: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch!
@changelog_1141_li @changelog_1155_li
#Fulltext search: in-memory Lucene indexes are now supported. #Fulltext search: in-memory Lucene indexes are now supported.
@changelog_1142_li @changelog_1156_li
#Fulltext search: UUID primary keys are now supported. #Fulltext search: UUID primary keys are now supported.
@changelog_1143_li @changelog_1157_li
#Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool. #Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool.
@changelog_1144_li @changelog_1158_li
#H2 Console: support the Midori browser (for Debian / Raspberry Pi) #H2 Console: support the Midori browser (for Debian / Raspberry Pi)
@changelog_1145_li @changelog_1159_li
#When opening a remote session, don't open a temporary file if the trace level is set to zero #When opening a remote session, don't open a temporary file if the trace level is set to zero
@changelog_1146_li @changelog_1160_li
#Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set. #Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set.
@changelog_1147_li @changelog_1161_li
#H2 Console: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents. #H2 Console: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents.
@changelog_1148_h2 @changelog_1162_h2
#Version 1.3.167 (2012-05-23) #Version 1.3.167 (2012-05-23)
@changelog_1149_li @changelog_1163_li
#H2 Console: when editing a row, an empty varchar column was replaced with a single space. #H2 Console: when editing a row, an empty varchar column was replaced with a single space.
@changelog_1150_li @changelog_1164_li
#Lukas Eder has updated the jOOQ documentation. #Lukas Eder has updated the jOOQ documentation.
@changelog_1151_li @changelog_1165_li
#Some nested joins could not be executed, for example: select * from (select * from (select * from a) a right join b b) c; #Some nested joins could not be executed, for example: select * from (select * from (select * from a) a right join b b) c;
@changelog_1152_li @changelog_1166_li
#MS SQL Server compatibility: ISNULL is now an alias for IFNULL. #MS SQL Server compatibility: ISNULL is now an alias for IFNULL.
@changelog_1153_li @changelog_1167_li
#Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot! #Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot!
@changelog_1154_li @changelog_1168_li
#Server mode: the number of CLOB / BLOB values that were cached on the server is now the maximum of: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS. #Server mode: the number of CLOB / BLOB values that were cached on the server is now the maximum of: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS.
@changelog_1155_li @changelog_1169_li
#In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2. #In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2.
@changelog_1156_li @changelog_1170_li
#The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required. #The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required.
@changelog_1157_li @changelog_1171_li
#Then reading from a resource using the prefix "classpath:", the ContextClassLoader is now used if the resource can't be read otherwise. #Then reading from a resource using the prefix "classpath:", the ContextClassLoader is now used if the resource can't be read otherwise.
@changelog_1158_li @changelog_1172_li
#DatabaseEventListener now calls setProgress whenever a statement starts and ends. #DatabaseEventListener now calls setProgress whenever a statement starts and ends.
@changelog_1159_li @changelog_1173_li
#DatabaseEventListener now calls setProgress periodically while a statement is running. #DatabaseEventListener now calls setProgress periodically while a statement is running.
@changelog_1160_li @changelog_1174_li
#The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME. #The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME.
@changelog_1161_li @changelog_1175_li
#Issue 378: when using views, the wrong values were bound to a parameter in some cases. #Issue 378: when using views, the wrong values were bound to a parameter in some cases.
@changelog_1162_li @changelog_1176_li
#Terrence Huang has translated the error messages to Chinese. Thanks a lot! #Terrence Huang has translated the error messages to Chinese. Thanks a lot!
@changelog_1163_li @changelog_1177_li
#TRUNC was added as an alias for TRUNCATE. #TRUNC was added as an alias for TRUNCATE.
@changelog_1164_li @changelog_1178_li
#Small optimisation for accessing result values by column name. #Small optimisation for accessing result values by column name.
@changelog_1165_li @changelog_1179_li
#Fix for bug in Statement.getMoreResults(int) #Fix for bug in Statement.getMoreResults(int)
@changelog_1166_li @changelog_1180_li
#The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch! #The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch!
@changelog_1167_h2 @changelog_1181_h2
#Version 1.3.166 (2012-04-08) #Version 1.3.166 (2012-04-08)
@changelog_1168_li @changelog_1182_li
#Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space. #Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space.
@changelog_1169_li @changelog_1183_li
#Server mode: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown. #Server mode: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown.
@changelog_1170_li @changelog_1184_li
#ConvertTraceFile: the time in the trace file is now parsed as a long. #ConvertTraceFile: the time in the trace file is now parsed as a long.
@changelog_1171_li @changelog_1185_li
#Invalid connection settings are now detected. #Invalid connection settings are now detected.
@changelog_1172_li @changelog_1186_li
#Issue 387: WHERE condition getting pushed into sub-query with LIMIT. #Issue 387: WHERE condition getting pushed into sub-query with LIMIT.
@changelog_1173_h2 @changelog_1187_h2
#Version 1.3.165 (2012-03-18) #Version 1.3.165 (2012-03-18)
@changelog_1174_li @changelog_1188_li
#Better string representation for decimal values (for example 0.00000000 instead of 0E-26). #Better string representation for decimal values (for example 0.00000000 instead of 0E-26).
@changelog_1175_li @changelog_1189_li
#Prepared statements could only be re-used if the same data types were used the second time they were executed. #Prepared statements could only be re-used if the same data types were used the second time they were executed.
@changelog_1176_li @changelog_1190_li
#In error messages about referential constraint violation, the values are now included. #In error messages about referential constraint violation, the values are now included.
@changelog_1177_li @changelog_1191_li
#SCRIPT and RUNSCRIPT: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement. #SCRIPT and RUNSCRIPT: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement.
@changelog_1178_li @changelog_1192_li
#MySQL compatibility: SUBSTR with a negative start index now works like MySQL. #MySQL compatibility: SUBSTR with a negative start index now works like MySQL.
@changelog_1179_li @changelog_1193_li
#When enabling autocommit, the transaction is now committed (as required by the JDBC API). #When enabling autocommit, the transaction is now committed (as required by the JDBC API).
@changelog_1180_li @changelog_1194_li
#The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch! #The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch!
@changelog_1181_li @changelog_1195_li
#If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB). #If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB).
@changelog_1182_li @changelog_1196_li
#ALTER TABLE ADD can now add more than one column at a time. #ALTER TABLE ADD can now add more than one column at a time.
@changelog_1183_li @changelog_1197_li
#Issue 380: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on. #Issue 380: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on.
@changelog_1184_li @changelog_1198_li
#Issue 384: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression. #Issue 384: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression.
@changelog_1185_li @changelog_1199_li
#Issue 362: support LIMIT in UPDATE statements. #Issue 362: support LIMIT in UPDATE statements.
@changelog_1186_li @changelog_1200_li
#Browser: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before). #Browser: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before).
@changelog_1187_li @changelog_1201_li
#CSV tool: new feature to disable writing the column header (option writeColumnHeader). #CSV tool: new feature to disable writing the column header (option writeColumnHeader).
@changelog_1188_li @changelog_1202_li
#CSV tool: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames). #CSV tool: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames).
@changelog_1189_li @changelog_1203_li
#PostgreSQL compatibility: LOG(x) is base 10 in the PostgreSQL mode. #PostgreSQL compatibility: LOG(x) is base 10 in the PostgreSQL mode.
@cheatSheet_1000_h1 @cheatSheet_1000_h1
...@@ -7019,7 +7061,7 @@ H2 データベース エンジン ...@@ -7019,7 +7061,7 @@ H2 データベース エンジン
#In-Memory Performance and Usage #In-Memory Performance and Usage
@mvstore_1060_p @mvstore_1060_p
# Performance of in-memory operations is comparable with <code>java.util.TreeMap</code> (many operations are actually faster), but usually slower than <code>java.util.HashMap</code>. # Performance of in-memory operations is comparable with <code>java.util.TreeMap</code>, but usually slower than <code>java.util.HashMap</code>.
@mvstore_1061_p @mvstore_1061_p
# The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory. # The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory.
...@@ -8663,7 +8705,7 @@ MySQL ...@@ -8663,7 +8705,7 @@ MySQL
#123 012 345 #123 012 345
@performance_1485_p @performance_1485_p
# Access by row id is fast because the data is sorted by this key. If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>: # Access by row id is fast because the data is sorted by this key. Please note the row id is not available until after the row was added (that means, it can not be used in computed columns or constraints). If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>:
@performance_1486_h3 @performance_1486_h3
#Indexes #Indexes
......
h2/src/docsrc/textbase/_docs_en.properties
浏览文件 @ 68d7ff3f
...@@ -554,194 +554,208 @@ build_1111_li=The rail images (one straight, four junctions, two turns) are gene ...@@ -554,194 +554,208 @@ build_1111_li=The rail images (one straight, four junctions, two turns) are gene
build_1112_p=\ To generate railroad diagrams for other grammars, see the package <code>org.h2.jcr</code>. This package is used to generate the SQL-2 railroad diagrams for the JCR 2.0 specification. build_1112_p=\ To generate railroad diagrams for other grammars, see the package <code>org.h2.jcr</code>. This package is used to generate the SQL-2 railroad diagrams for the JCR 2.0 specification.
changelog_1000_h1=Change Log changelog_1000_h1=Change Log
changelog_1001_h2=Next Version (unreleased) changelog_1001_h2=Next Version (unreleased)
changelog_1002_li=Improved spatial index and data type. changelog_1002_li=The function "regexp_replace" threw the wrong kind of exception if the replacement string was invalid.
changelog_1003_li=Issue 467\: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle). changelog_1003_li=A checkpoint is now done every MAX_LOG_SIZE / 2 instead of every MAX_LOG_SIZE, so that the transaction log doesn't grow as large.
changelog_1004_li=Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases. changelog_1004_li=MVStore table engine\: new setting "retention_time" to configure the time to retain old data. The default is 45 seconds.
changelog_1005_li=Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG changelog_1005_li=The method TableEngine.createTable() now returns a Table object.
changelog_1006_li=Bug\: Changes to the database structure did not result in the Session query cache being invalidated. changelog_1006_li=For read-only databases, for the trace level "debug", the trace info is written to the temp directory.
changelog_1007_li=New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis. changelog_1007_li=Closing the file lock will now wait until the background thread is stopped.
changelog_1008_h2=Version 1.3.173 (2013-07-28) changelog_1008_li=In version 1.3.172, a performance regression was introduced when fixing the issue 389 (when there is a multi-column primary key, H2 does not seem to always pick the right index). This was related to boosting an index that matches the "order by" column list (the wrong index was used in some cases).
changelog_1009_li=Support empty statements that just contains a comment. changelog_1009_li=Improved spatial index and data type.
changelog_1010_li=Server mode\: if there was an error while reading from a LOB, the session was closed in some cases. changelog_1010_li=Issue 467\: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).
changelog_1011_li=Issue 463\: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData. changelog_1011_li=Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases.
changelog_1012_li=JaQu\: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set). changelog_1012_li=Fix bug in unique and non-unique hash indexes which manifested as incorrect results when the search key was a different cardinal type from the table index key. e.g. where the one was INT and the other was LONG
changelog_1013_li=For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine. changelog_1013_li=Bug\: Changes to the database structure did not result in the Session query cache being invalidated.
changelog_1014_li=New column "information_schema.tables.row_count_estimate". changelog_1014_li=New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis.
changelog_1015_li=Issue 468\: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException. changelog_1015_li=When running the Recover tool on very large (>6G) databases, some statistics were reported with negative numbers.
changelog_1016_li=The expression trunc(number) threw a NullPointerException. changelog_1016_li=Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue sessions are creating large transactions.
changelog_1017_li=Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2(). changelog_1017_li=Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
changelog_1018_li=Fixed a deadlock related to very large temporary result sets. changelog_1018_li=When the H2 parser fails to parse a SQL statement, throw a more specific exception that contains extra information to make it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
changelog_1019_li=Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file. changelog_1019_li=Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
changelog_1020_li=Issue 474\: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski. changelog_1020_li=Session-temporary LOB's could sometimes accumulate, increasing the size of the DB file until shutdown. Now they are cleared out at every commit.
changelog_1021_li=Issue 476\: Broken link in jaqu.html changelog_1021_li=There was a bug where a hash index with more than one column would be silently converted to a regular index. It will now throw an exception.
changelog_1022_li=Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess. changelog_1022_h2=Version 1.3.173 (2013-07-28)
changelog_1023_li=Improve error message when check constraint is broken, test case from Gili (cowwoc). changelog_1023_li=Support empty statements that just contains a comment.
changelog_1024_li=Improve error message when we have a unique constraint violation, displays the offending key in the error message. changelog_1024_li=Server mode\: if there was an error while reading from a LOB, the session was closed in some cases.
changelog_1025_li=Issue 478\: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin. changelog_1025_li=Issue 463\: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData.
changelog_1026_li=Issue 475\: PgServer\: add support for CancelRequest, patch from Andrew Franklin. changelog_1026_li=JaQu\: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set).
changelog_1027_li=Issue 473\: PgServer missing -key option, patch from Andrew Franklin. changelog_1027_li=For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine.
changelog_1028_li=Issue 471\: CREATE VIEW does not check user rights, patch from Andrew Franklin. changelog_1028_li=New column "information_schema.tables.row_count_estimate".
changelog_1029_li=Issue 477\: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin. changelog_1029_li=Issue 468\: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException.
changelog_1030_li=Issue 479\: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin. changelog_1030_li=The expression trunc(number) threw a NullPointerException.
changelog_1031_li=Issue 472\: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin. changelog_1031_li=Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2().
changelog_1032_li=Add syntax for passing additional parameters into custom TableEngine implementations. changelog_1032_li=Fixed a deadlock related to very large temporary result sets.
changelog_1033_li=Issue 480\: Bugfix post issue 475, 477, patch from Andrew Franklin. changelog_1033_li=Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file.
changelog_1034_li=Issue 481\: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin. changelog_1034_li=Issue 474\: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski.
changelog_1035_li=Add support for spatial datatype GEOMETRY. changelog_1035_li=Issue 476\: Broken link in jaqu.html
changelog_1036_li=Add support for in-memory spatial index. changelog_1036_li=Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess.
changelog_1037_li=change the PageStore\#changeCount field from an int to a long, to cope with databases with very high transaction rates. changelog_1037_li=Improve error message when check constraint is broken, test case from Gili (cowwoc).
changelog_1038_li=Fix a NullPointerException when attempting to add foreign key reference to a view. changelog_1038_li=Improve error message when we have a unique constraint violation, displays the offending key in the error message.
changelog_1039_li=Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy. changelog_1039_li=Issue 478\: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin.
changelog_1040_li=Issue 482\: class LobStorageBackend$LobInputStream does not override the method InputStream.available(). changelog_1040_li=Issue 475\: PgServer\: add support for CancelRequest, patch from Andrew Franklin.
changelog_1041_li=Fix corruption resulting from a mix of the "WRITE_DELAY\=0" option and "SELECT DISTINCT" queries that don't fit in memory. changelog_1041_li=Issue 473\: PgServer missing -key option, patch from Andrew Franklin.
changelog_1042_li=Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works. changelog_1042_li=Issue 471\: CREATE VIEW does not check user rights, patch from Andrew Franklin.
changelog_1043_li=Issue 484\: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d" changelog_1043_li=Issue 477\: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin.
changelog_1044_li=MySQL compatibility, support the "AUTO_INCREMENT\=3" part of the CREATE TABLE statement. changelog_1044_li=Issue 479\: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin.
changelog_1045_li=Issue 486\: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement. changelog_1045_li=Issue 472\: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin.
changelog_1046_li=Issue 487\: support the MySQL "SET foreign_key_checks \= 0" command changelog_1046_li=Add syntax for passing additional parameters into custom TableEngine implementations.
changelog_1047_li=Issue 490\: support MySQL "USING BTREE" index declaration changelog_1047_li=Issue 480\: Bugfix post issue 475, 477, patch from Andrew Franklin.
changelog_1048_li=Issue 485\: Database get corrupted when column is renamed for which check constraint was defined inside create table statement. changelog_1048_li=Issue 481\: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin.
changelog_1049_li=Issue 499\: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax changelog_1049_li=Add support for spatial datatype GEOMETRY.
changelog_1050_li=Issue 501\: "CREATE TABLE .. WITH" not serialized, patch from nico.devel changelog_1050_li=Add support for in-memory spatial index.
changelog_1051_li=Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable. changelog_1051_li=change the PageStore\#changeCount field from an int to a long, to cope with databases with very high transaction rates.
changelog_1052_h2=Version 1.3.172 (2013-05-25) changelog_1052_li=Fix a NullPointerException when attempting to add foreign key reference to a view.
changelog_1053_li=Referential integrity\: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed. changelog_1053_li=Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.
changelog_1054_li=The auto-analyze feature now only reads 1000 rows per table instead of 10000. changelog_1054_li=Issue 482\: class LobStorageBackend$LobInputStream does not override the method InputStream.available().
changelog_1055_li=The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list". changelog_1055_li=Fix corruption resulting from a mix of the "WRITE_DELAY\=0" option and "SELECT DISTINCT" queries that don't fit in memory.
changelog_1056_li=Issue 454\: Use Charset for type-safety. changelog_1056_li=Fix the combination of updating a table which contains an LOB, and reading from the LOB at the same time. Previously it would throw an exception, now it works.
changelog_1057_li=Queries with both LIMIT and OFFSET could throw an IllegalArgumentException. changelog_1057_li=Issue 484\: In the H2 Console tool, all schemas starting with "INFO" where hidden. Now they are hidden only if the database is not H2. Patch from "mgcodeact"/"cumer d"
changelog_1058_li=MVStore\: multiple issues were fixed\: 460, 461, 462, 464, 466. changelog_1058_li=MySQL compatibility, support the "AUTO_INCREMENT\=3" part of the CREATE TABLE statement.
changelog_1059_li=MVStore\: larger stores (multiple GB) are now much faster. changelog_1059_li=Issue 486\: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
changelog_1060_li=When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool). changelog_1060_li=Issue 487\: support the MySQL "SET foreign_key_checks \= 0" command
changelog_1061_li=Support TRUNC(timestamp) for improved Oracle compatibility. changelog_1061_li=Issue 490\: support MySQL "USING BTREE" index declaration
changelog_1062_li=Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long. changelog_1062_li=Issue 485\: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
changelog_1063_li=Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode. changelog_1063_li=Issue 499\: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax
changelog_1064_li=Issue 453\: ABBA race conditions in TABLE LINK connection sharing. changelog_1064_li=Issue 501\: "CREATE TABLE .. WITH" not serialized, patch from nico.devel
changelog_1065_li=Issue 449\: Postgres Serial data type should not automatically be marked as primary key changelog_1065_li=Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.
changelog_1066_li=Issue 406\: Support "select h2version()" changelog_1066_h2=Version 1.3.172 (2013-05-25)
changelog_1067_li=Issue 389\: When there is a multi-column primary key, H2 does not seem to always pick the right index changelog_1067_li=Referential integrity\: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed.
changelog_1068_li=Issue 305\: Implement SELECT ... FOR FETCH ONLY changelog_1068_li=The auto-analyze feature now only reads 1000 rows per table instead of 10000.
changelog_1069_li=Issue 274\: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions changelog_1069_li=The optimization for IN(...) queries combined with OR could result in a strange exception of the type "column x must be included in the group by list".
changelog_1070_li=Issue 274\: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function. changelog_1070_li=Issue 454\: Use Charset for type-safety.
changelog_1071_li=Issue 274\: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)" changelog_1071_li=Queries with both LIMIT and OFFSET could throw an IllegalArgumentException.
changelog_1072_li=Fix bug in Optimizing SELECT * FROM A WHERE X\=1 OR X\=2 OR X\=3 into SELECT * FROM A WHERE X IN (1,2,3) changelog_1072_li=MVStore\: multiple issues were fixed\: 460, 461, 462, 464, 466.
changelog_1073_li=Issue 442\: Groovy patch for SourceCompiler (function ALIAS) changelog_1073_li=MVStore\: larger stores (multiple GB) are now much faster.
changelog_1074_li=Issue 459\: Improve LOB documentation changelog_1074_li=When using local temporary tables and not dropping them manually before closing the session, and then killing the process could result in a database that couldn't be opened (except when using the recover tool).
changelog_1075_h2=Version 1.3.171 (2013-03-17) changelog_1075_li=Support TRUNC(timestamp) for improved Oracle compatibility.
changelog_1076_li=Security\: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers". changelog_1076_li=Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long.
changelog_1077_li=H2 Console\: the session timeout can now be configured using the system property "h2.consoleTimeout". changelog_1077_li=Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode.
changelog_1078_li=Issue 431\: Improved compatibility with MySQL\: support for "ENGINE\=InnoDB charset\=UTF8" when creating a table. changelog_1078_li=Issue 453\: ABBA race conditions in TABLE LINK connection sharing.
changelog_1079_li=Issue 249\: Improved compatibility with MySQL in the MySQL mode\: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode. changelog_1079_li=Issue 449\: Postgres Serial data type should not automatically be marked as primary key
changelog_1080_li=Issue 434\: H2 Console didn't work in the Chrome browser due to a wrong viewport argument. changelog_1080_li=Issue 406\: Support "select h2version()"
changelog_1081_li=There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database. changelog_1081_li=Issue 389\: When there is a multi-column primary key, H2 does not seem to always pick the right index
changelog_1082_li=The SQL script generated by the "script" command contained inconsistent newlines on Windows. changelog_1082_li=Issue 305\: Implement SELECT ... FOR FETCH ONLY
changelog_1083_li=When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made. changelog_1083_li=Issue 274\: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions
changelog_1084_li=Optimize IN(...) queries\: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed. changelog_1084_li=Issue 274\: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function.
changelog_1085_li=Optimize IN(...) queries\: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed. changelog_1085_li=Issue 274\: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)"
changelog_1086_li=Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23\:00\:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem\! changelog_1086_li=Fix bug in Optimizing SELECT * FROM A WHERE X\=1 OR X\=2 OR X\=3 into SELECT * FROM A WHERE X IN (1,2,3)
changelog_1087_li=New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE\=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db". changelog_1087_li=Issue 442\: Groovy patch for SourceCompiler (function ALIAS)
changelog_1088_li=New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine. changelog_1088_li=Issue 459\: Improve LOB documentation
changelog_1089_li=MVStore\: encrypted stores are now supported. Only standardized algorithms are used\: PBKDF2, SHA-256, XTS-AES, AES-128. changelog_1089_h2=Version 1.3.171 (2013-03-17)
changelog_1090_li=MVStore\: improved API thanks to Simo Tripodi. changelog_1090_li=Security\: the TCP server did not correctly restrict access rights of clients in some cases. This was specially a problem when using the flag "tcpAllowOthers".
changelog_1091_li=MVStore\: maps can now be renamed. changelog_1091_li=H2 Console\: the session timeout can now be configured using the system property "h2.consoleTimeout".
changelog_1092_li=MVStore\: store the file header also at the end of each chunk, which results in a further reduced number of write operations. changelog_1092_li=Issue 431\: Improved compatibility with MySQL\: support for "ENGINE\=InnoDB charset\=UTF8" when creating a table.
changelog_1093_li=MVStore\: a map implementation that supports concurrent operations. changelog_1093_li=Issue 249\: Improved compatibility with MySQL in the MySQL mode\: now the methods DatabaseMetaData methods stores*Case*Identifiers return the same as MySQL when using the MySQL mode.
changelog_1094_li=MVStore\: unified exception handling; the version is included in the messages. changelog_1094_li=Issue 434\: H2 Console didn't work in the Chrome browser due to a wrong viewport argument.
changelog_1095_li=MVStore\: old data is now retained for 45 seconds by default. changelog_1095_li=There was a possibility that the .lock.db file was not deleted when the database was closed, which could slow down opening the database.
changelog_1096_li=MVStore\: compress is now disabled by default, and can be enabled on request. changelog_1096_li=The SQL script generated by the "script" command contained inconsistent newlines on Windows.
changelog_1097_li=Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401. changelog_1097_li=When using trace level 4 (SLF4J) in the server mode, a directory "trace.db" and an empty file was created on the client side. This is no longer made.
changelog_1098_li=Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365. changelog_1098_li=Optimize IN(...) queries\: there was a bug in version 1.3.170 if the type of the left hand side didn't match the type of the right hand side. Fixed.
changelog_1099_li=Add a DISK_SPACE_USED system function. Fixes issue 270. changelog_1099_li=Optimize IN(...) queries\: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed.
changelog_1100_li=Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder. changelog_1100_li=Timestamps with timezone that were passed as a string were not always converted correctly. For example "2012-11-06T23\:00\:00.000Z" was converted to "2012-11-06" instead of to "2012-11-07" in the timezone CET. Thanks a lot to Steve Hruda for reporting the problem\!
changelog_1101_li=Supporting dropping an index for Lucene full-text indexes. changelog_1101_li=New table engine "org.h2.mvstore.db.MVTableEngine" that internally uses the MVStore to persist data. To try it out, append ";DEFAULT_TABLE_ENGINE\=org.h2.mvstore.db.MVTableEngine" to the database URL. This is still very experimental, and many features are not supported yet. The data is stored in a file with the suffix ".mv.db".
changelog_1102_li=Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin). changelog_1102_li=New connection setting "DEFAULT_TABLE_ENGINE" to use a specific table engine if none is set explicitly. This is to simplify testing the MVStore table engine.
changelog_1103_li=Experimental off-heap memory storage engine "nioMemFS\:" and "nioMemLZF\:", suggestion from Mark Addleman. changelog_1103_li=MVStore\: encrypted stores are now supported. Only standardized algorithms are used\: PBKDF2, SHA-256, XTS-AES, AES-128.
changelog_1104_li=Issue 438\: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169. changelog_1104_li=MVStore\: improved API thanks to Simo Tripodi.
changelog_1105_li=MySQL compatibility\: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela. changelog_1105_li=MVStore\: maps can now be renamed.
changelog_1106_li=Issue 404\: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS\=NUMBERS. changelog_1106_li=MVStore\: store the file header also at the end of each chunk, which results in a further reduced number of write operations.
changelog_1107_li=Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW. changelog_1107_li=MVStore\: a map implementation that supports concurrent operations.
changelog_1108_li=Issue 439\: Utils.sortTopN does not handle single-element arrays. changelog_1108_li=MVStore\: unified exception handling; the version is included in the messages.
changelog_1109_h2=Version 1.3.170 (2012-11-30) changelog_1109_li=MVStore\: old data is now retained for 45 seconds by default.
changelog_1110_li=Issue 407\: The TriggerAdapter didn't work with CLOB and BLOB columns. changelog_1110_li=MVStore\: compress is now disabled by default, and can be enabled on request.
changelog_1111_li=PostgreSQL compatibility\: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT. changelog_1111_li=Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401.
changelog_1112_li=Issue 417\: H2 Console\: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened. changelog_1112_li=Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365.
changelog_1113_li=Issue 412\: Running the Server tool with just the option "-browser" will now log a warning. changelog_1113_li=Add a DISK_SPACE_USED system function. Fixes issue 270.
changelog_1114_li=Issue 411\: CloseWatcher registration was not concurrency-safe. changelog_1114_li=Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder.
changelog_1115_li=MySQL compatibility\: support for CONCAT_WS. Thanks a lot to litailang for the patch\! changelog_1115_li=Supporting dropping an index for Lucene full-text indexes.
changelog_1116_li=PostgreSQL compatibility\: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch\! changelog_1116_li=Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin).
changelog_1117_li=Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints. changelog_1117_li=Experimental off-heap memory storage engine "nioMemFS\:" and "nioMemLZF\:", suggestion from Mark Addleman.
changelog_1118_li=Support BOM at the beginning of files for the RUNSCRIPT command changelog_1118_li=Issue 438\: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169.
changelog_1119_li=Fix in calling SET @X \= IDENTITY() where it would return NULL incorrectly changelog_1119_li=MySQL compatibility\: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela.
changelog_1120_li=Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread. changelog_1120_li=Issue 404\: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS\=NUMBERS.
changelog_1121_li=Optimize IN(...) queries where the values are constant and of the same type. changelog_1121_li=Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW.
changelog_1122_li=Restore tool\: the parameter "quiet" was not used and is now removed. changelog_1122_li=Issue 439\: Utils.sortTopN does not handle single-element arrays.
changelog_1123_li=Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych. changelog_1123_h2=Version 1.3.170 (2012-11-30)
changelog_1124_li=Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch\! changelog_1124_li=Issue 407\: The TriggerAdapter didn't work with CLOB and BLOB columns.
changelog_1125_h2=Version 1.3.169 (2012-09-09) changelog_1125_li=PostgreSQL compatibility\: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT.
changelog_1126_li=The default jar file is now compiled for Java 6. changelog_1126_li=Issue 417\: H2 Console\: the web session timeout didn't work, resulting in a memory leak. This was only a problem if the H2 Console was run for a long time and many sessions were opened.
changelog_1127_li=The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http\://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http\://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual. changelog_1127_li=Issue 412\: Running the Server tool with just the option "-browser" will now log a warning.
changelog_1128_li=A part of the documentation and the H2 Console has been changed to support the Apple retina display. changelog_1128_li=Issue 411\: CloseWatcher registration was not concurrency-safe.
changelog_1129_li=The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode. changelog_1129_li=MySQL compatibility\: support for CONCAT_WS. Thanks a lot to litailang for the patch\!
changelog_1130_li=Statement.getQueryTimeout()\: only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot. changelog_1130_li=PostgreSQL compatibility\: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch\!
changelog_1131_li=Issue 416\: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file. changelog_1131_li=Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints.
changelog_1132_li=Issue 414\: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice). changelog_1132_li=Support BOM at the beginning of files for the RUNSCRIPT command
changelog_1133_li=The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API. changelog_1133_li=Fix in calling SET @X \= IDENTITY() where it would return NULL incorrectly
changelog_1134_li=Added compatibility for "SET NAMES" query in MySQL compatibility mode. changelog_1134_li=Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread.
changelog_1135_h2=Version 1.3.168 (2012-07-13) changelog_1135_li=Optimize IN(...) queries where the values are constant and of the same type.
changelog_1136_li=The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log. changelog_1136_li=Restore tool\: the parameter "quiet" was not used and is now removed.
changelog_1137_li=New system property "h2.serializeJavaObject" (default\: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used. changelog_1137_li=Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych.
changelog_1138_li=Dylan has translated the H2 Console tool to Korean. Thanks a lot\! changelog_1138_li=Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch\!
changelog_1139_li=Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database. changelog_1139_h2=Version 1.3.169 (2012-09-09)
changelog_1140_li=MVCC\: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch\! changelog_1140_li=The default jar file is now compiled for Java 6.
changelog_1141_li=Fulltext search\: in-memory Lucene indexes are now supported. changelog_1141_li=The new jar file will probably not end up in the central Maven repository in the next few weeks because Sonatype has disabled automatic synchronization from SourceForge (which they call 'legacy sync' now). It will probably take some time until this is sorted out. The H2 jar files are deployed to http\://h2database.com/m2-repo/com/h2database/h2/maven-metadata.xml and http\://hsql.sourceforge.net/m2-repo/com/h2database/h2/maven-metadata.xml as usual.
changelog_1142_li=Fulltext search\: UUID primary keys are now supported. changelog_1142_li=A part of the documentation and the H2 Console has been changed to support the Apple retina display.
changelog_1143_li=Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool. changelog_1143_li=The CreateCluster tool could not be used if the source database contained a CLOB or BLOB. The root cause was that the TCP server did not synchronize on the session, which caused a problem when using the exclusive mode.
changelog_1144_li=H2 Console\: support the Midori browser (for Debian / Raspberry Pi) changelog_1144_li=Statement.getQueryTimeout()\: only the first call to this method will query the database. If the query timeout was changed in another way than calling setQueryTimeout, this method will always return the last value. This was changed because Hibernate calls getQueryTimeout() a lot.
changelog_1145_li=When opening a remote session, don't open a temporary file if the trace level is set to zero changelog_1145_li=Issue 416\: PreparedStatement.setNString throws AbstractMethodError. All implemented JDBC 4 methods that don't break compatibility with Java 5 are now included in the default jar file.
changelog_1146_li=Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set. changelog_1146_li=Issue 414\: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice).
changelog_1147_li=H2 Console\: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents. changelog_1147_li=The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API.
changelog_1148_h2=Version 1.3.167 (2012-05-23) changelog_1148_li=Added compatibility for "SET NAMES" query in MySQL compatibility mode.
changelog_1149_li=H2 Console\: when editing a row, an empty varchar column was replaced with a single space. changelog_1149_h2=Version 1.3.168 (2012-07-13)
changelog_1150_li=Lukas Eder has updated the jOOQ documentation. changelog_1150_li=The message "Transaction log could not be truncated" was sometimes written to the .trace.db file even if there was no problem truncating the transaction log.
changelog_1151_li=Some nested joins could not be executed, for example\: select * from (select * from (select * from a) a right join b b) c; changelog_1151_li=New system property "h2.serializeJavaObject" (default\: true) that allows to disable serializing Java objects, so that the objects compareTo and toString methods can be used.
changelog_1152_li=MS SQL Server compatibility\: ISNULL is now an alias for IFNULL. changelog_1152_li=Dylan has translated the H2 Console tool to Korean. Thanks a lot\!
changelog_1153_li=Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot\! changelog_1153_li=Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database.
changelog_1154_li=Server mode\: the number of CLOB / BLOB values that were cached on the server is now the maximum of\: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS. changelog_1154_li=MVCC\: concurrently updating a row could result in the row to appear deleted in the second connection, if there are multiple unique indexes (or a primary key and at least one unique index). Thanks a lot to Teruo for the patch\!
changelog_1155_li=In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2. changelog_1155_li=Fulltext search\: in-memory Lucene indexes are now supported.
changelog_1156_li=The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required. changelog_1156_li=Fulltext search\: UUID primary keys are now supported.
changelog_1157_li=Then reading from a resource using the prefix "classpath\:", the ContextClassLoader is now used if the resource can't be read otherwise. changelog_1157_li=Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool.
changelog_1158_li=DatabaseEventListener now calls setProgress whenever a statement starts and ends. changelog_1158_li=H2 Console\: support the Midori browser (for Debian / Raspberry Pi)
changelog_1159_li=DatabaseEventListener now calls setProgress periodically while a statement is running. changelog_1159_li=When opening a remote session, don't open a temporary file if the trace level is set to zero
changelog_1160_li=The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME. changelog_1160_li=Use HMAC for authenticating remote LOB id's, removing the need for maintaining a cache, and removing the limit on the number of LOBs per result set.
changelog_1161_li=Issue 378\: when using views, the wrong values were bound to a parameter in some cases. changelog_1161_li=H2 Console\: HTML and XML documents can now be edited in an updatable result set. There is (limited) support for editing multi-line documents.
changelog_1162_li=Terrence Huang has translated the error messages to Chinese. Thanks a lot\! changelog_1162_h2=Version 1.3.167 (2012-05-23)
changelog_1163_li=TRUNC was added as an alias for TRUNCATE. changelog_1163_li=H2 Console\: when editing a row, an empty varchar column was replaced with a single space.
changelog_1164_li=Small optimisation for accessing result values by column name. changelog_1164_li=Lukas Eder has updated the jOOQ documentation.
changelog_1165_li=Fix for bug in Statement.getMoreResults(int) changelog_1165_li=Some nested joins could not be executed, for example\: select * from (select * from (select * from a) a right join b b) c;
changelog_1166_li=The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch\! changelog_1166_li=MS SQL Server compatibility\: ISNULL is now an alias for IFNULL.
changelog_1167_h2=Version 1.3.166 (2012-04-08) changelog_1167_li=Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot\!
changelog_1168_li=Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space. changelog_1168_li=Server mode\: the number of CLOB / BLOB values that were cached on the server is now the maximum of\: 5 times the SERVER_RESULT_SET_FETCH_SIZE (which is 100 by default), and SysProperties.SERVER_CACHED_OBJECTS.
changelog_1169_li=Server mode\: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown. changelog_1169_li=In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2.
changelog_1170_li=ConvertTraceFile\: the time in the trace file is now parsed as a long. changelog_1170_li=The feature LOG_SIZE_LIMIT that was introduced in version 1.3.165 did not always work correctly (specially with regards to multithreading) and has been removed. The message "Transaction log could not be truncated" is still written to the .trace.db file if required.
changelog_1171_li=Invalid connection settings are now detected. changelog_1171_li=Then reading from a resource using the prefix "classpath\:", the ContextClassLoader is now used if the resource can't be read otherwise.
changelog_1172_li=Issue 387\: WHERE condition getting pushed into sub-query with LIMIT. changelog_1172_li=DatabaseEventListener now calls setProgress whenever a statement starts and ends.
changelog_1173_h2=Version 1.3.165 (2012-03-18) changelog_1173_li=DatabaseEventListener now calls setProgress periodically while a statement is running.
changelog_1174_li=Better string representation for decimal values (for example 0.00000000 instead of 0E-26). changelog_1174_li=The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME.
changelog_1175_li=Prepared statements could only be re-used if the same data types were used the second time they were executed. changelog_1175_li=Issue 378\: when using views, the wrong values were bound to a parameter in some cases.
changelog_1176_li=In error messages about referential constraint violation, the values are now included. changelog_1176_li=Terrence Huang has translated the error messages to Chinese. Thanks a lot\!
changelog_1177_li=SCRIPT and RUNSCRIPT\: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement. changelog_1177_li=TRUNC was added as an alias for TRUNCATE.
changelog_1178_li=MySQL compatibility\: SUBSTR with a negative start index now works like MySQL. changelog_1178_li=Small optimisation for accessing result values by column name.
changelog_1179_li=When enabling autocommit, the transaction is now committed (as required by the JDBC API). changelog_1179_li=Fix for bug in Statement.getMoreResults(int)
changelog_1180_li=The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch\! changelog_1180_li=The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch\!
changelog_1181_li=If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT\=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB). changelog_1181_h2=Version 1.3.166 (2012-04-08)
changelog_1182_li=ALTER TABLE ADD can now add more than one column at a time. changelog_1182_li=Indexes on column that are larger than half the page size (wide indexes) could sometimes get corrupt, resulting in an ArrayIndexOutOfBoundsException in PageBtree.getRow or "Row not found" in PageBtreeLeaf. Also, such indexes used too much disk space.
changelog_1183_li=Issue 380\: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on. changelog_1183_li=Server mode\: when retrieving more than 64 rows each containing a CLOB or BLOB, the error message "The object is already closed" was thrown.
changelog_1184_li=Issue 384\: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression. changelog_1184_li=ConvertTraceFile\: the time in the trace file is now parsed as a long.
changelog_1185_li=Issue 362\: support LIMIT in UPDATE statements. changelog_1185_li=Invalid connection settings are now detected.
changelog_1186_li=Browser\: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before). changelog_1186_li=Issue 387\: WHERE condition getting pushed into sub-query with LIMIT.
changelog_1187_li=CSV tool\: new feature to disable writing the column header (option writeColumnHeader). changelog_1187_h2=Version 1.3.165 (2012-03-18)
changelog_1188_li=CSV tool\: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames). changelog_1188_li=Better string representation for decimal values (for example 0.00000000 instead of 0E-26).
changelog_1189_li=PostgreSQL compatibility\: LOG(x) is base 10 in the PostgreSQL mode. changelog_1189_li=Prepared statements could only be re-used if the same data types were used the second time they were executed.
changelog_1190_li=In error messages about referential constraint violation, the values are now included.
changelog_1191_li=SCRIPT and RUNSCRIPT\: the password can now be set using a prepared statement. Previously, it was required to be a literal in the SQL statement.
changelog_1192_li=MySQL compatibility\: SUBSTR with a negative start index now works like MySQL.
changelog_1193_li=When enabling autocommit, the transaction is now committed (as required by the JDBC API).
changelog_1194_li=The shell script <code>h2.sh</code> did not work with spaces in the path. It also works now with quoted spaces in the argument list. Thanks a lot to Shimizu Fumiyuki for the patch\!
changelog_1195_li=If the transaction log could not be truncated because of an uncommitted transaction, now "Transaction log could not be truncated" is written to the .trace.db file. Before, the database file was growing and it was hard to find out what the root cause was. To avoid the database file from growing, a new feature to automatically rollback the oldest transaction is available now. To enable it, append ;LOG_SIZE_LIMIT\=32 to the database URL (in that case, the oldest session is rolled back if the transaction log is 32 MB).
changelog_1196_li=ALTER TABLE ADD can now add more than one column at a time.
changelog_1197_li=Issue 380\: ALTER TABLE ADD FOREIGN KEY with an explicit index didn't verify the index can be used, which would lead to a NullPointerException later on.
changelog_1198_li=Issue 384\: the wrong kind of exception (NullPointerException) was thrown in a UNION query with an incorrect ORDER BY expression.
changelog_1199_li=Issue 362\: support LIMIT in UPDATE statements.
changelog_1200_li=Browser\: if no default browser is set, Google Chrome is now used if available. If not available, then Konqueror, Netscape, or Opera is used if available (as before).
changelog_1201_li=CSV tool\: new feature to disable writing the column header (option writeColumnHeader).
changelog_1202_li=CSV tool\: new feature to preserve the case sensitivity of column names (option caseSensitiveColumnNames).
changelog_1203_li=PostgreSQL compatibility\: LOG(x) is base 10 in the PostgreSQL mode.
cheatSheet_1000_h1=H2 Database Engine Cheat Sheet cheatSheet_1000_h1=H2 Database Engine Cheat Sheet
cheatSheet_1001_h2=Using H2 cheatSheet_1001_h2=Using H2
cheatSheet_1002_a=H2 cheatSheet_1002_a=H2
...@@ -2338,7 +2352,7 @@ mvstore_1056_h3=Transactions ...@@ -2338,7 +2352,7 @@ mvstore_1056_h3=Transactions
mvstore_1057_p=\ To support multiple concurrent open transactions, a transaction utility is included, the <code>TransactionStore</code>. The tool supports PostgreSQL style "read committed" transaction isolation with savepoints, two-phase commit, and other features typically available in a database. There is no limit on the size of a transaction (the log is written to disk for large or long running transactions). mvstore_1057_p=\ To support multiple concurrent open transactions, a transaction utility is included, the <code>TransactionStore</code>. The tool supports PostgreSQL style "read committed" transaction isolation with savepoints, two-phase commit, and other features typically available in a database. There is no limit on the size of a transaction (the log is written to disk for large or long running transactions).
mvstore_1058_p=\ Internally, this utility stores the old versions of changed entries in a separate map, similar to a transaction log (except that entries of a closed transaction are removed, and the log is usually not stored for short transactions). For common use cases, the storage overhead of this utility is very small compared to the overhead of a regular transaction log. mvstore_1058_p=\ Internally, this utility stores the old versions of changed entries in a separate map, similar to a transaction log (except that entries of a closed transaction are removed, and the log is usually not stored for short transactions). For common use cases, the storage overhead of this utility is very small compared to the overhead of a regular transaction log.
mvstore_1059_h3=In-Memory Performance and Usage mvstore_1059_h3=In-Memory Performance and Usage
mvstore_1060_p=\ Performance of in-memory operations is comparable with <code>java.util.TreeMap</code> (many operations are actually faster), but usually slower than <code>java.util.HashMap</code>. mvstore_1060_p=\ Performance of in-memory operations is comparable with <code>java.util.TreeMap</code>, but usually slower than <code>java.util.HashMap</code>.
mvstore_1061_p=\ The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory. mvstore_1061_p=\ The memory overhead for large maps is slightly better than for the regular map implementations, but there is a higher overhead per map. For maps with less than about 25 entries, the regular map implementations need less memory.
mvstore_1062_p=\ If no file name is specified, the store operates purely in memory. Except for persisting data, all features are supported in this mode (multi-versioning, index lookup, R-tree and so on). If a file name is specified, all operations occur in memory (with the same performance characteristics) until data is persisted. mvstore_1062_p=\ If no file name is specified, the store operates purely in memory. Except for persisting data, all features are supported in this mode (multi-versioning, index lookup, R-tree and so on). If a file name is specified, all operations occur in memory (with the same performance characteristics) until data is persisted.
mvstore_1063_h3=Pluggable Data Types mvstore_1063_h3=Pluggable Data Types
...@@ -2886,7 +2900,7 @@ performance_1481_td=Philip ...@@ -2886,7 +2900,7 @@ performance_1481_td=Philip
performance_1482_td=Jones performance_1482_td=Jones
performance_1483_td=Berne performance_1483_td=Berne
performance_1484_td=123 012 345 performance_1484_td=123 012 345
performance_1485_p=\ Access by row id is fast because the data is sorted by this key. If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>\: performance_1485_p=\ Access by row id is fast because the data is sorted by this key. Please note the row id is not available until after the row was added (that means, it can not be used in computed columns or constraints). If the query condition does not contain the row id (and if no other index can be used), then all rows of the table are scanned. A table scan iterates over all rows in the table, in the order of the row id. To find out what strategy the database uses to retrieve the data, use <code>EXPLAIN SELECT</code>\:
performance_1486_h3=Indexes performance_1486_h3=Indexes
performance_1487_p=\ An index internally is basically just a table that contains the indexed column(s), plus the row id\: performance_1487_p=\ An index internally is basically just a table that contains the indexed column(s), plus the row id\:
performance_1488_p=\ In the index, the data is sorted by the indexed columns. So this index contains the following data\: performance_1488_p=\ In the index, the data is sorted by the indexed columns. So this index contains the following data\:
......
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