Subqueries or views with "order by" an alias expression could not be executed due to a regression introduced in version 1.3.174.
@changelog_1003_h2
Version 1.3.174 (2013-10-19)
@changelog_1003_li
Issue 73: MySQL compatibility: support REPLACE, patch by Cemo Koc.
@changelog_1004_li
LIRS cache: bugfix for caches that only contain non-resident entries.
The spatial index now works in MVCC mode when using the MVStore storage.
@changelog_1005_li
For in-memory databases, queries with a "group by" column that is also a hash index threw a RuntimeException.
MVStore: concurrency problems have been fixed. The API has been simplified.
@changelog_1006_li
Improved error message for some syntax errors.
Improve error message when dropping an index that belongs to a constraint, specify constraint in error message.
@changelog_1007_li
File system abstraction: if used directly, some file systems did not work correctly with spliced byte buffers (the database engine doesn't use those).
Issue 518: java.sql.Connection.commit() freezes after LOB modification with EXCLUSIVE connection
@changelog_1008_li
To use the MVStore storage engine (which is still work in progress), append ";mv_store=true" to the database URL. Using the MVTableEngine when creating the table is no longer recommended.
Issue 517: Create or replace view statement has no effect on the others already existing JDBC connection
@changelog_1009_li
To compile user defined functions, the javax.tools.JavaCompiler is now used if available, and no temporary files are created. This should solve problems when multiple H2 database concurrently compile the same user defined functions. To disable, system the system property "h2.javaSystemCompiler" to false.
Support 123L syntax as in Java; example: SELECT (2000000000L*2).
@changelog_1010_li
Concurrently creating function aliases in different databases could result in the exception "javac: file not found".
Issue 520: Add support for sequence max value, min value and cycle, patch by Daniel Gredler.
@changelog_1011_li
The function "regexp_replace" threw the wrong kind of exception if the replacement string was invalid.
@changelog_1011_h2
Version 1.3.174 (2013-10-19)
@changelog_1012_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.
LIRS cache: bugfix for caches that only contain non-resident entries.
@changelog_1013_li
MVStore table engine: new setting "retention_time" to configure the time to retain old data. The default is 45 seconds.
For in-memory databases, queries with a "group by" column that is also a hash index threw a RuntimeException.
@changelog_1014_li
The method TableEngine.createTable() now returns a Table object.
Improved error message for some syntax errors.
@changelog_1015_li
For read-only databases, for the trace level "debug", the trace info is written to the temp directory.
File system abstraction: if used directly, some file systems did not work correctly with spliced byte buffers (the database engine doesn't use those).
@changelog_1016_li
Closing the file lock will now wait until the background thread is stopped.
To use the MVStore storage engine (which is still work in progress), append ";mv_store=true" to the database URL. Using the MVTableEngine when creating the table is no longer recommended.
@changelog_1017_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).
To compile user defined functions, the javax.tools.JavaCompiler is now used if available, and no temporary files are created. This should solve problems when multiple H2 database concurrently compile the same user defined functions. To disable, system the system property "h2.javaSystemCompiler" to false.
@changelog_1018_li
Improved spatial index and data type.
Concurrently creating function aliases in different databases could result in the exception "javac: file not found".
@changelog_1019_li
Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).
The function "regexp_replace" threw the wrong kind of exception if the replacement string was invalid.
@changelog_1020_li
Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases.
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_1021_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
MVStore table engine: new setting "retention_time" to configure the time to retain old data. The default is 45 seconds.
@changelog_1022_li
Bug: Changes to the database structure did not result in the Session query cache being invalidated.
The method TableEngine.createTable() now returns a Table object.
@changelog_1023_li
New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis.
For read-only databases, for the trace level "debug", the trace info is written to the temp directory.
@changelog_1024_li
When running the Recover tool on very large (>6G) databases, some statistics were reported with negative numbers.
Closing the file lock will now wait until the background thread is stopped.
@changelog_1025_li
Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue sessions are creating large transactions.
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_1026_li
Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
Improved spatial index and data type.
@changelog_1027_li
The BNF tool and the autocomplete feature are exported in OSGi, which makes it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
Issue 467: OSGi Class Loader (ability to create reference to class in other ClassLoader, for example in another OSGi bundle).
@changelog_1028_li
Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
Queries "group by" that contain a subquery with an aggregate function returned the wrong result in some cases.
@changelog_1029_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.
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_1030_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.
Bug: Changes to the database structure did not result in the Session query cache being invalidated.
@changelog_1031_li
Query Statistics: new feature which stores the newest 100 SQL queries executed and their performance data. Useful for tracking down badly performing queries.
New feature from Davide Cavestro - allow using custom Java object serialization engines on a per-DB basis.
@changelog_1032_li
Fix an LOB deadlock between reading and updating LOB columns.
When running the Recover tool on very large (>6G) databases, some statistics were reported with negative numbers.
@changelog_1033_li
Support the JDBC DatabaseMetaData#getClientInfoProperties() method, in the sense of returning an empty result, in order to make WebSphere happy.
Add a CONTAINS_UNCOMMITTED column to the SESSIONS metadata table, to allow detecting when rogue sessions are creating large transactions.
@changelog_1034_li
Make Server#openBrowser respect the $BROWSER environment variable. Add "chromium" to the list of browsers tried. Patch from Felix Kaiser.
Some small fixes to the GEOMETRY support, patches by Nicolas Fortin.
@changelog_1035_li
Fix to org.h2.util.ScriptReader when handling unclosed block comments.
The BNF tool and the autocomplete feature are exported in OSGi, which makes it possible for smart editors to do autocomplete. Patch from Nicolas Fortin.
@changelog_1036_li
Make org.h2.util.ScriptReader throw a better exception when handling broken scripts which generate extremely large statements.
Fix DROP ALL OBJECTS and DROP SCHEMA in the presence of tables with computed column dependencies.
@changelog_1037_li
Fix bug with ALLOW_LITERALS=NONE, where the periodic analyze table on insert would throw an exception. A similar problem was fixed in the Console tool.
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_1038_li
Issue 510: Make org.h2.bnf public for consumption by external projects, patch by Nicolas Fortin
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_1039_li
Issue 509: Important fix on ValueGeometry, patch by Nicolas Fortin (with some tweaking) Make ValueGeometry#getDimensionCount more reliable. Add unit test to check for illegal ValueGeometry comparison Add unit test for conversion of Geometry object into Object Add optional export to MANIFEST.MF for JTS Geometry classes Validate that geometry values can be represented in WKB.
Query Statistics: new feature which stores the newest 100 SQL queries executed and their performance data. Useful for tracking down badly performing queries.
@changelog_1040_li
Issue 506: RFE: Include Thread.getName() in case of a deadlock
Fix an LOB deadlock between reading and updating LOB columns.
@changelog_1041_li
Adding support for "GRANT ALTER ANY SCHEMA TO <user>", patch by John Yates
Support the JDBC DatabaseMetaData#getClientInfoProperties() method, in the sense of returning an empty result, in order to make WebSphere happy.
@changelog_1042_h2
Version 1.3.173 (2013-07-28)
@changelog_1042_li
Make Server#openBrowser respect the $BROWSER environment variable. Add "chromium" to the list of browsers tried. Patch from Felix Kaiser.
@changelog_1043_li
Support empty statements that just contains a comment.
Fix to org.h2.util.ScriptReader when handling unclosed block comments.
@changelog_1044_li
Server mode: if there was an error while reading from a LOB, the session was closed in some cases.
Make org.h2.util.ScriptReader throw a better exception when handling broken scripts which generate extremely large statements.
@changelog_1045_li
Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData.
Fix bug with ALLOW_LITERALS=NONE, where the periodic analyze table on insert would throw an exception. A similar problem was fixed in the Console tool.
@changelog_1046_li
JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set).
Issue 510: Make org.h2.bnf public for consumption by external projects, patch by Nicolas Fortin
@changelog_1047_li
For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine.
Issue 509: Important fix on ValueGeometry, patch by Nicolas Fortin (with some tweaking) Make ValueGeometry#getDimensionCount more reliable. Add unit test to check for illegal ValueGeometry comparison Add unit test for conversion of Geometry object into Object Add optional export to MANIFEST.MF for JTS Geometry classes Validate that geometry values can be represented in WKB.
@changelog_1048_li
New column "information_schema.tables.row_count_estimate".
Issue 506: RFE: Include Thread.getName() in case of a deadlock
@changelog_1049_li
Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException.
Adding support for "GRANT ALTER ANY SCHEMA TO <user>", patch by John Yates
@changelog_1050_li
The expression trunc(number) threw a NullPointerException.
@changelog_1050_h2
Version 1.3.173 (2013-07-28)
@changelog_1051_li
Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2().
Support empty statements that just contains a comment.
@changelog_1052_li
Fixed a deadlock related to very large temporary result sets.
Server mode: if there was an error while reading from a LOB, the session was closed in some cases.
@changelog_1053_li
Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file.
Issue 463: Driver name and version are now the same in OsgiDataSourceFactory and JdbcDatabaseMetaData.
@changelog_1054_li
Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski.
JaQu: The data type VARCHAR is now (again) used for Strings (no longer TEXT, except when explicitly set).
@changelog_1055_li
Issue 476: Broken link in jaqu.html
For in-memory databases, creating an index on a CLOB or BLOB column is no longer supported. This is to simplify the MVTableEngine.
@changelog_1056_li
Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess.
New column "information_schema.tables.row_count_estimate".
@changelog_1057_li
Improve error message when check constraint is broken, test case from Gili (cowwoc).
Issue 468: trunc(timestamp) could return the wrong value (+12 hours), and trunc(number) throw a NullPointerException.
@changelog_1058_li
Improve error message when we have a unique constraint violation, displays the offending key in the error message.
The expression trunc(number) threw a NullPointerException.
@changelog_1059_li
Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin.
Fixed a deadlock when updating LOB's concurrently. See TestLob.testDeadlock2().
@changelog_1060_li
Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin.
Fixed a deadlock related to very large temporary result sets.
@changelog_1061_li
Issue 473: PgServer missing -key option, patch from Andrew Franklin.
Add "-list" command line option to Shell tool so that result-list-mode can be triggered when reading from a file.
@changelog_1062_li
Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin.
Issue 474: H2 MySQL Compatibility code fails to ignore "COMMENT" in CREATE TABLE, patch from Aaron Azeckoski.
@changelog_1063_li
Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin.
Issue 476: Broken link in jaqu.html
@changelog_1064_li
Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin.
Fix potential UTF8 encoding issue in org.h2.store.FileStore, reported by Juerg Spiess.
@changelog_1065_li
Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin.
Improve error message when check constraint is broken, test case from Gili (cowwoc).
@changelog_1066_li
Add syntax for passing additional parameters into custom TableEngine implementations.
Improve error message when we have a unique constraint violation, displays the offending key in the error message.
@changelog_1067_li
Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin.
Issue 478: Support for "SHOW TRANSACTION ISOLATION LEVEL", patch from Andrew Franklin.
@changelog_1068_li
Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin.
Issue 475: PgServer: add support for CancelRequest, patch from Andrew Franklin.
@changelog_1069_li
Add support for spatial datatype GEOMETRY.
Issue 473: PgServer missing -key option, patch from Andrew Franklin.
@changelog_1070_li
Add support for in-memory spatial index.
Issue 471: CREATE VIEW does not check user rights, patch from Andrew Franklin.
@changelog_1071_li
change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates.
Issue 477: PgServer binary transmission of query params is unimplemented, patch from Andrew Franklin.
@changelog_1072_li
Fix a NullPointerException when attempting to add foreign key reference to a view.
Issue 479: Support for SUBSTRING without a FROM condition, patch from Andrew Franklin.
@changelog_1073_li
Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.
Issue 472: PgServer does not work with any recent Postgres JDBC driver, patch from Andrew Franklin.
@changelog_1074_li
Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available().
Add syntax for passing additional parameters into custom TableEngine implementations.
@changelog_1075_li
Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory.
Issue 480: Bugfix post issue 475, 477, patch from Andrew Franklin.
@changelog_1076_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.
Issue 481: Further extensions to PgServer to support better support PG JDBC, patch from Andrew Franklin.
@changelog_1077_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"
Add support for spatial datatype GEOMETRY.
@changelog_1078_li
MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement.
Add support for in-memory spatial index.
@changelog_1079_li
Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
change the PageStore#changeCount field from an int to a long, to cope with databases with very high transaction rates.
@changelog_1080_li
Issue 487: support the MySQL "SET foreign_key_checks = 0" command
Fix a NullPointerException when attempting to add foreign key reference to a view.
@changelog_1081_li
Issue 490: support MySQL "USING BTREE" index declaration
Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.
@changelog_1082_li
Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
Issue 482: class LobStorageBackend$LobInputStream does not override the method InputStream.available().
@changelog_1083_li
Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax
Fix corruption resulting from a mix of the "WRITE_DELAY=0" option and "SELECT DISTINCT" queries that don't fit in memory.
@changelog_1084_li
Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel
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_1085_li
Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.
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_1086_h2
Version 1.3.172 (2013-05-25)
@changelog_1086_li
MySQL compatibility, support the "AUTO_INCREMENT=3" part of the CREATE TABLE statement.
@changelog_1087_li
Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed.
Issue 486: MySQL compatibility, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
@changelog_1088_li
The auto-analyze feature now only reads 1000 rows per table instead of 10000.
Issue 487: support the MySQL "SET foreign_key_checks = 0" command
@changelog_1089_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".
Issue 490: support MySQL "USING BTREE" index declaration
@changelog_1090_li
Issue 454: Use Charset for type-safety.
Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
@changelog_1091_li
Queries with both LIMIT and OFFSET could throw an IllegalArgumentException.
Issue 499: support MySQL "UNIQUE KEY (ID) USING BTREE" constraint syntax
@changelog_1092_li
MVStore: multiple issues were fixed: 460, 461, 462, 464, 466.
Issue 501: "CREATE TABLE .. WITH" not serialized, patch from nico.devel
@changelog_1093_li
MVStore: larger stores (multiple GB) are now much faster.
Avoid problems with runtime-compiled ALIAS methods when people have set the JAVA_TOOL_OPTIONS environment variable.
@changelog_1094_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_1094_h2
Version 1.3.172 (2013-05-25)
@changelog_1095_li
Support TRUNC(timestamp) for improved Oracle compatibility.
Referential integrity: when adding a referential integrity constraint failed, and if creating the constraint automatically created an index, this index was not removed.
@changelog_1096_li
Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long.
The auto-analyze feature now only reads 1000 rows per table instead of 10000.
@changelog_1097_li
Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode.
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_1098_li
Issue 453: ABBA race conditions in TABLE LINK connection sharing.
Issue 454: Use Charset for type-safety.
@changelog_1099_li
Issue 449: Postgres Serial data type should not automatically be marked as primary key
Queries with both LIMIT and OFFSET could throw an IllegalArgumentException.
@changelog_1100_li
Issue 406: Support "select h2version()"
MVStore: multiple issues were fixed: 460, 461, 462, 464, 466.
@changelog_1101_li
Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index
MVStore: larger stores (multiple GB) are now much faster.
@changelog_1102_li
Issue 305: Implement SELECT ... FOR FETCH ONLY
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_1103_li
Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions
Support TRUNC(timestamp) for improved Oracle compatibility.
@changelog_1104_li
Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function.
Add support for CREATE TABLE TEST (ID BIGSERIAL) for PostgreSQL compatibility. Patch from Jesse Long.
@changelog_1105_li
Issue 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)"
Add new collation command SET BINARY_COLLATION UNSIGNED, helps with people testing BINARY columns in MySQL mode.
@changelog_1106_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)
Issue 453: ABBA race conditions in TABLE LINK connection sharing.
@changelog_1107_li
Issue 442: Groovy patch for SourceCompiler (function ALIAS)
Issue 449: Postgres Serial data type should not automatically be marked as primary key
@changelog_1108_li
Issue 459: Improve LOB documentation
Issue 406: Support "select h2version()"
@changelog_1109_h2
Version 1.3.171 (2013-03-17)
@changelog_1109_li
Issue 389: When there is a multi-column primary key, H2 does not seem to always pick the right index
@changelog_1110_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".
Issue 305: Implement SELECT ... FOR FETCH ONLY
@changelog_1111_li
H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout".
Issue 274: Sybase/MSSQLServer compatibility - Add GETDATE and CHARINDEX system functions
@changelog_1112_li
Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table.
Issue 274: Sybase/MSSQLServer compatibility - swap parameters of CONVERT function.
@changelog_1113_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 274: Sybase/MSSQLServer compatibility - support index clause e.g. "select * from test (index table1_index)"
@changelog_1114_li
Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument.
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_1115_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.
Issue 442: Groovy patch for SourceCompiler (function ALIAS)
@changelog_1116_li
The SQL script generated by the "script" command contained inconsistent newlines on Windows.
Issue 459: Improve LOB documentation
@changelog_1117_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_1117_h2
Version 1.3.171 (2013-03-17)
@changelog_1118_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.
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_1119_li
Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed.
H2 Console: the session timeout can now be configured using the system property "h2.consoleTimeout".
@changelog_1120_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!
Issue 431: Improved compatibility with MySQL: support for "ENGINE=InnoDB charset=UTF8" when creating a table.
@changelog_1121_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".
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_1122_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.
Issue 434: H2 Console didn't work in the Chrome browser due to a wrong viewport argument.
@changelog_1123_li
MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128.
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_1124_li
MVStore: improved API thanks to Simo Tripodi.
The SQL script generated by the "script" command contained inconsistent newlines on Windows.
@changelog_1125_li
MVStore: maps can now be renamed.
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_1126_li
MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations.
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_1127_li
MVStore: a map implementation that supports concurrent operations.
Optimize IN(...) queries: there was a bug in version 1.3.170 for comparison of the type "X IN(NULL, NULL)". Fixed.
@changelog_1128_li
MVStore: unified exception handling; the version is included in the messages.
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_1129_li
MVStore: old data is now retained for 45 seconds by default.
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_1130_li
MVStore: compress is now disabled by default, and can be enabled on request.
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_1131_li
Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401.
MVStore: encrypted stores are now supported. Only standardized algorithms are used: PBKDF2, SHA-256, XTS-AES, AES-128.
@changelog_1132_li
Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365.
MVStore: improved API thanks to Simo Tripodi.
@changelog_1133_li
Add a DISK_SPACE_USED system function. Fixes issue 270.
MVStore: maps can now be renamed.
@changelog_1134_li
Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder.
MVStore: store the file header also at the end of each chunk, which results in a further reduced number of write operations.
@changelog_1135_li
Supporting dropping an index for Lucene full-text indexes.
MVStore: a map implementation that supports concurrent operations.
@changelog_1136_li
Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin).
MVStore: unified exception handling; the version is included in the messages.
@changelog_1137_li
Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman.
MVStore: old data is now retained for 45 seconds by default.
@changelog_1138_li
Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169.
MVStore: compress is now disabled by default, and can be enabled on request.
@changelog_1139_li
MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela.
Support ALTER TABLE ADD ... AFTER. Patch from Andrew Gaul (argaul at gmail.com). Fixes issue 401.
@changelog_1140_li
Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS.
Improved OSGi support. H2 now registers itself as a DataSourceFactory service. Fixes issue 365.
@changelog_1141_li
Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW.
Add a DISK_SPACE_USED system function. Fixes issue 270.
@changelog_1142_li
Fix a compile-time ambiguity when compiling with JDK7, thanks to a patch from Lukas Eder.
@changelog_1143_li
Supporting dropping an index for Lucene full-text indexes.
@changelog_1144_li
Optimized performance for SELECT ... ORDER BY X LIMIT Y OFFSET Z queries for in-memory databases using partial sort (by Sergi Vladykin).
@changelog_1145_li
Experimental off-heap memory storage engine "nioMemFS:" and "nioMemLZF:", suggestion from Mark Addleman.
@changelog_1146_li
Issue 438: JdbcDatabaseMetaData.getSchemas() is no longer supported as of 1.3.169.
@changelog_1147_li
MySQL compatibility: support for ALTER TABLE tableName MODIFY [COLUMN] columnName columnDef. Patch from Ville Koskela.
@changelog_1148_li
Issue 404: SHOW COLUMNS FROM tableName does not work with ALLOW_LITERALS=NUMBERS.
@changelog_1149_li
Throw an explicit error to make it clear we don't support the TRIGGER combination of SELECT and FOR EACH ROW.
@changelog_1150_li
Issue 439: Utils.sortTopN does not handle single-element arrays.
@changelog_1143_h2
@changelog_1151_h2
Version 1.3.170 (2012-11-30)
@changelog_1144_li
@changelog_1152_li
Issue 407: The TriggerAdapter didn't work with CLOB and BLOB columns.
@changelog_1145_li
@changelog_1153_li
PostgreSQL compatibility: support for data types BIGSERIAL and SERIAL as an alias for AUTO_INCREMENT.
@changelog_1146_li
@changelog_1154_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_1147_li
@changelog_1155_li
Issue 412: Running the Server tool with just the option "-browser" will now log a warning.
@changelog_1148_li
@changelog_1156_li
Issue 411: CloseWatcher registration was not concurrency-safe.
@changelog_1149_li
@changelog_1157_li
MySQL compatibility: support for CONCAT_WS. Thanks a lot to litailang for the patch!
@changelog_1150_li
@changelog_1158_li
PostgreSQL compatibility: support for EXTRACT(WEEK FROM dateColumn). Thanks to Prashant Bhat for the patch!
@changelog_1151_li
@changelog_1159_li
Fix for a bug where we would sometimes use the wrong unique constraint to validate foreign key constraints.
@changelog_1152_li
@changelog_1160_li
Support BOM at the beginning of files for the RUNSCRIPT command
@changelog_1153_li
@changelog_1161_li
Fix in calling SET @X = IDENTITY() where it would return NULL incorrectly
@changelog_1154_li
@changelog_1162_li
Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread.
@changelog_1155_li
@changelog_1163_li
Optimize IN(...) queries where the values are constant and of the same type.
@changelog_1156_li
@changelog_1164_li
Restore tool: the parameter "quiet" was not used and is now removed.
@changelog_1157_li
@changelog_1165_li
Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by Viktor Voytovych.
@changelog_1158_li
@changelog_1166_li
Serialization is now pluggable using the system property "h2.javaObjectSerializer". Thanks to Sergi Vladykin for the patch!
@changelog_1159_h2
@changelog_1167_h2
Version 1.3.169 (2012-09-09)
@changelog_1160_li
@changelog_1168_li
The default jar file is now compiled for Java 6.
@changelog_1161_li
@changelog_1169_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_1162_li
@changelog_1170_li
A part of the documentation and the H2 Console has been changed to support the Apple retina display.
@changelog_1163_li
@changelog_1171_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_1164_li
@changelog_1172_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_1165_li
@changelog_1173_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_1166_li
@changelog_1174_li
Issue 414: for some functions, the parameters were evaluated twice (for example "char(nextval(..))" ran "nextval(..)" twice).
@changelog_1167_li
@changelog_1175_li
The ResultSetMetaData methods getSchemaName and getTableName could return null instead of "" (an empty string) as specified in the JDBC API.
@changelog_1168_li
@changelog_1176_li
Added compatibility for "SET NAMES" query in MySQL compatibility mode.
@changelog_1169_h2
@changelog_1177_h2
Version 1.3.168 (2012-07-13)
@changelog_1170_li
@changelog_1178_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_1171_li
@changelog_1179_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_1172_li
@changelog_1180_li
Dylan has translated the H2 Console tool to Korean. Thanks a lot!
@changelog_1173_li
@changelog_1181_li
Executing the statement CREATE INDEX IF ALREADY EXISTS if the index already exists no longer fails for a read only database.
@changelog_1174_li
@changelog_1182_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_1175_li
@changelog_1183_li
Fulltext search: in-memory Lucene indexes are now supported.
@changelog_1176_li
@changelog_1184_li
Fulltext search: UUID primary keys are now supported.
@changelog_1177_li
@changelog_1185_li
Apache Tomcat 7.x will now longer log a warning when unloading the web application, if using a connection pool.
@changelog_1178_li
@changelog_1186_li
H2 Console: support the Midori browser (for Debian / Raspberry Pi)
@changelog_1179_li
@changelog_1187_li
When opening a remote session, don't open a temporary file if the trace level is set to zero
@changelog_1180_li
@changelog_1188_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_1181_li
@changelog_1189_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_1182_h2
@changelog_1190_h2
Version 1.3.167 (2012-05-23)
@changelog_1183_li
@changelog_1191_li
H2 Console: when editing a row, an empty varchar column was replaced with a single space.
@changelog_1184_li
@changelog_1192_li
Lukas Eder has updated the jOOQ documentation.
@changelog_1185_li
@changelog_1193_li
Some nested joins could not be executed, for example: select * from (select * from (select * from a) a right join b b) c;
@changelog_1186_li
@changelog_1194_li
MS SQL Server compatibility: ISNULL is now an alias for IFNULL.
@changelog_1187_li
@changelog_1195_li
Terrence Huang has completed the translation of the H2 Console tool to Chinese. Thanks a lot!
@changelog_1188_li
@changelog_1196_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_1189_li
@changelog_1197_li
In the trace file, the query execution time was incorrect in some cases, specially for the statement SET TRACE_LEVEL_FILE 2.
@changelog_1190_li
@changelog_1198_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_1191_li
@changelog_1199_li
Then reading from a resource using the prefix "classpath:", the ContextClassLoader is now used if the resource can't be read otherwise.
@changelog_1192_li
@changelog_1200_li
DatabaseEventListener now calls setProgress whenever a statement starts and ends.
@changelog_1193_li
@changelog_1201_li
DatabaseEventListener now calls setProgress periodically while a statement is running.
@changelog_1194_li
@changelog_1202_li
The table INFORMATION_SCHEMA.FUNCTION_ALIASES now includes a column TYPE_NAME.
@changelog_1195_li
@changelog_1203_li
Issue 378: when using views, the wrong values were bound to a parameter in some cases.
@changelog_1196_li
@changelog_1204_li
Terrence Huang has translated the error messages to Chinese. Thanks a lot!
@changelog_1197_li
@changelog_1205_li
TRUNC was added as an alias for TRUNCATE.
@changelog_1198_li
@changelog_1206_li
Small optimisation for accessing result values by column name.
@changelog_1199_li
@changelog_1207_li
Fix for bug in Statement.getMoreResults(int)
@changelog_1200_li
@changelog_1208_li
The SCRIPT statements now supports filtering by schema and table. Thanks a lot to Jacob Qvortrup for providing the patch!
@cheatSheet_1000_h1
...
...
@@ -7172,7 +7196,7 @@ Old versions of the data can be read concurrently with all other operations.
Transaction are supported (including concurrent transactions and 2-phase commit).
@mvstore_1032_li
The tool is very modular. It supports pluggable data types / serialization, pluggable storage (to a file, to off-heap memory), pluggable map implementations (B-tree, R-tree, concurrent B-tree currently), BLOB storage, and a file system abstraction to support encrypted files and zip files.
The tool is very modular. It supports pluggable data types and serialization, pluggable storage (to a file, to off-heap memory), pluggable map implementations (B-tree, R-tree, concurrent B-tree currently), BLOB storage, and a file system abstraction to support encrypted files and zip files.
@mvstore_1033_h2
Example Code
...
...
@@ -7187,89 +7211,89 @@ Store Builder
The <code>MVStore.Builder</code> provides a fluid interface to build a store if more complex configuration options are used. The following code contains all supported configuration options:
@mvstore_1037_li
backgroundExceptionListener: a listener for exceptions that could occur while writing in the background.
autoCommitDisabled(): to disable auto-commit.
@mvstore_1038_li
cacheSize: the cache size in MB.
backgroundExceptionListener: a listener for exceptions that could occur while writing in the background.
@mvstore_1039_li
compressData: compress the data when storing.
cacheSize: the cache size in MB.
@mvstore_1040_li
encryptionKey: the encryption key for file encryption.
compressData: compress the data when storing.
@mvstore_1041_li
fileName: the name of the file, for file based stores.
encryptionKey: the encryption key for file encryption.
@mvstore_1042_li
fileStore: the storage implementation to use.
fileName: the name of the file, for file based stores.
@mvstore_1043_li
pageSplitSize: the point where pages are split.
fileStore: the storage implementation to use.
@mvstore_1044_li
readOnly: open the file in read-only mode.
pageSplitSize: the point where pages are split.
@mvstore_1045_li
writeBufferSize: the size of the write buffer in MB.
@mvstore_1046_li
writeDelay: the maximum delay in milliseconds until committed changes are stored in the background.
readOnly: open the file in read-only mode.
@mvstore_1047_h2
@mvstore_1046_h2
R-Tree
@mvstore_1048_p
@mvstore_1047_p
The <code>MVRTreeMap</code> is an R-tree implementation that supports fast spatial queries. It can be used as follows:
@mvstore_1049_p
@mvstore_1048_p
The default number of dimensions is 2. To use a different number of dimensions, call <code>new MVRTreeMap.Builder<String>().dimensions(3)</code>. The minimum number of dimensions is 1, the maximum is 255.
@mvstore_1050_h2
@mvstore_1049_h2
Features
@mvstore_1051_h3
@mvstore_1050_h3
Maps
@mvstore_1052_p
@mvstore_1051_p
Each store contains a set of named maps. A map is sorted by key, and supports the common lookup operations, including access to the first and last key, iterate over some or all keys, and so on.
@mvstore_1053_p
@mvstore_1052_p
Also supported, and very uncommon for maps, is fast index lookup: the entries of the map can be be efficiently accessed like a random-access list (get the entry at the given index), and the index of a key can be calculated efficiently. That also means getting the median of two keys is very fast, and a range of keys can be counted very quickly. The iterator supports fast skipping. This is possible because internally, each map is organized in the form of a counted B+-tree.
@mvstore_1054_p
@mvstore_1053_p
In database terms, a map can be used like a table, where the key of the map is the primary key of the table, and the value is the row. A map can also represent an index, where the key of the map is the key of the index, and the value of the map is the primary key of the table (for non-unique indexes, the key of the map must also contain the primary key).
@mvstore_1055_h3
@mvstore_1054_h3
Versions
@mvstore_1056_p
Multiple versions are supported. A version is a snapshot of all the data of all maps at a given point in time. Versions are not immediately persisted; instead, only the version counter is incremented. If there is a change after switching to a new version, a snapshot of the old version is kept in memory, so that it can still be read. Old persisted versions are readable until the old data was explicitly overwritten. Creating a snapshot is fast: only the pages that are changed after a snapshot are copied. This behavior is also called COW (copy on write). Rollback is supported (rollback to any old in-memory version or an old persisted version).
@mvstore_1055_p
A version is a snapshot of all the data of all maps at a given point in time. Old versions are readable until the old data was explicitly overwritten. Creating a snapshot is fast: only those pages that are changed after a snapshot are copied. This behavior is also called COW (copy on write). Rollback to an old version is supported.
@mvstore_1057_p
@mvstore_1056_p
The following sample code show how to create a store, open a map, add some data, and access the current and an old version:
@mvstore_1058_h3
@mvstore_1057_h3
Transactions
@mvstore_1059_p
@mvstore_1058_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_1060_p
@mvstore_1059_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_1061_h3
@mvstore_1060_h3
In-Memory Performance and Usage
@mvstore_1062_p
@mvstore_1061_p
Performance of in-memory operations is comparable with <code>java.util.TreeMap</code>, but usually slower than <code>java.util.HashMap</code>.
@mvstore_1063_p
@mvstore_1062_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_1064_p
@mvstore_1063_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_1064_p
As in all map implementations, changing the key object after an entry has been added to the map is not allowed (keys are immutable). If a file name is specified, the value may also not be changed after adding an entry, because it might be serialized at any time.
@mvstore_1065_h3
Pluggable Data Types
...
...
@@ -9341,7 +9365,7 @@ Linked schema using CSV files: one schema for a directory of files; support inde
iReport to support H2.
@roadmap_1072_li
Include SMPT (mail) client (alert on cluster failure, low disk space,...).
Include SMTP (mail) client (alert on cluster failure, low disk space,...).
@roadmap_1073_li
Option for SCRIPT to only process one or a set of schemas or tables, and append to a file.
...
...
@@ -9419,1284 +9443,1278 @@ Test and document UPDATE TEST SET (ID, NAME) = (SELECT ID*10, NAME || '!' FROM T
Max memory rows / max undo log size: use block count / row size not row count.
@roadmap_1098_li
Support 123L syntax as in Java; example: SELECT (2000000000*2).
@roadmap_1099_li
Implement point-in-time recovery.
@roadmap_1100_li
@roadmap_1099_li
Support PL/SQL (programming language / control flow statements).
@roadmap_1101_li
@roadmap_1100_li
LIKE: improved version for larger texts (currently using naive search).
@roadmap_1102_li
@roadmap_1101_li
Throw an exception when the application calls getInt on a Long (optional).
@roadmap_1103_li
@roadmap_1102_li
Default date format for input and output (local date constants).
@roadmap_1104_li
@roadmap_1103_li
Document ROWNUM usage for reports: SELECT ROWNUM, * FROM (subquery).
@roadmap_1105_li
@roadmap_1104_li
File system that writes to two file systems (replication, replicating file system).
@roadmap_1106_li
@roadmap_1105_li
Standalone tool to get relevant system properties and add it to the trace output.
@roadmap_1107_li
@roadmap_1106_li
Support 'call proc(1=value)' (PostgreSQL, Oracle).
@roadmap_1108_li
@roadmap_1107_li
Console: improve editing data (Tab, Shift-Tab, Enter, Up, Down, Shift+Del?).
Implement Clob / Blob truncate and the remaining functionality.
@roadmap_1125_li
@roadmap_1124_li
Add multiple columns at the same time with ALTER TABLE .. ADD .. ADD ...
@roadmap_1126_li
@roadmap_1125_li
File locking: writing a system property to detect concurrent access from the same VM (different classloaders).
@roadmap_1127_li
@roadmap_1126_li
Pure SQL triggers (example: update parent table if the child table is changed).
@roadmap_1128_li
@roadmap_1127_li
Add H2 to Gem (Ruby install system).
@roadmap_1129_li
@roadmap_1128_li
Support linked JCR tables.
@roadmap_1130_li
@roadmap_1129_li
Native fulltext search: min word length; store word positions.
@roadmap_1131_li
@roadmap_1130_li
Add an option to the SCRIPT command to generate only portable / standard SQL.
@roadmap_1132_li
@roadmap_1131_li
Updatable views: create 'instead of' triggers automatically if possible (simple cases first).
@roadmap_1133_li
@roadmap_1132_li
Improve create index performance.
@roadmap_1134_li
@roadmap_1133_li
Compact databases without having to close the database (vacuum).
@roadmap_1135_li
@roadmap_1134_li
Implement more JDBC 4.0 features.
@roadmap_1136_li
@roadmap_1135_li
Support TRANSFORM / PIVOT as in MS Access.
@roadmap_1137_li
@roadmap_1136_li
SELECT * FROM (VALUES (...), (...), ....) AS alias(f1, ...).
@roadmap_1138_li
@roadmap_1137_li
Support updatable views with join on primary keys (to extend a table).
@roadmap_1139_li
@roadmap_1138_li
Public interface for functions (not public static).
@roadmap_1140_li
@roadmap_1139_li
Support reading the transaction log.
@roadmap_1141_li
@roadmap_1140_li
Feature matrix as in <a href="http://www.inetsoftware.de/products/jdbc/mssql/features/default.asp">i-net software</a>.
@roadmap_1142_li
@roadmap_1141_li
Updatable result set on table without primary key or unique index.
@roadmap_1143_li
@roadmap_1142_li
Compatibility with Derby and PostgreSQL: VALUES(1), (2); SELECT * FROM (VALUES (1), (2)) AS myTable(c1). Issue 221.
@roadmap_1144_li
@roadmap_1143_li
Allow execution time prepare for SELECT * FROM CSVREAD(?, 'columnNameString')
@roadmap_1145_li
@roadmap_1144_li
Support data type INTERVAL
@roadmap_1146_li
@roadmap_1145_li
Support nested transactions (possibly using savepoints internally).
@roadmap_1147_li
@roadmap_1146_li
Add a benchmark for bigger databases, and one for many users.
@roadmap_1148_li
@roadmap_1147_li
Compression in the result set over TCP/IP.
@roadmap_1149_li
@roadmap_1148_li
Support curtimestamp (like curtime, curdate).
@roadmap_1150_li
@roadmap_1149_li
Support ANALYZE {TABLE|INDEX} tableName COMPUTE|ESTIMATE|DELETE STATISTICS ptnOption options.
@roadmap_1151_li
@roadmap_1150_li
Release locks (shared or exclusive) on demand
@roadmap_1152_li
@roadmap_1151_li
Support OUTER UNION
@roadmap_1153_li
@roadmap_1152_li
Support parameterized views (similar to CSVREAD, but using just SQL for the definition)
@roadmap_1154_li
@roadmap_1153_li
A way (JDBC driver) to map an URL (jdbc:h2map:c1) to a connection object
@roadmap_1155_li
@roadmap_1154_li
Support dynamic linked schema (automatically adding/updating/removing tables)
@roadmap_1156_li
@roadmap_1155_li
Clustering: adding a node should be very fast and without interrupting clients (very short lock)
@roadmap_1157_li
@roadmap_1156_li
Compatibility: # is the start of a single line comment (MySQL) but date quote (Access). Mode specific
@roadmap_1158_li
@roadmap_1157_li
Run benchmarks with Android, Java 7, java -server
@roadmap_1159_li
@roadmap_1158_li
Optimizations: faster hash function for strings.
@roadmap_1160_li
@roadmap_1159_li
DatabaseEventListener: callback for all operations (including expected time, RUNSCRIPT) and cancel functionality
@roadmap_1161_li
@roadmap_1160_li
Benchmark: add a graph to show how databases scale (performance/database size)
@roadmap_1162_li
@roadmap_1161_li
Implement a SQLData interface to map your data over to a custom object
@roadmap_1163_li
@roadmap_1162_li
In the MySQL and PostgreSQL mode, use lower case identifiers by default (DatabaseMetaData.storesLowerCaseIdentifiers = true)
@roadmap_1164_li
@roadmap_1163_li
Support multiple directories (on different hard drives) for the same database
@roadmap_1165_li
@roadmap_1164_li
Server protocol: use challenge response authentication, but client sends hash(user+password) encrypted with response
@roadmap_1166_li
@roadmap_1165_li
Support EXEC[UTE] (doesn't return a result set, compatible to MS SQL Server)
@roadmap_1167_li
@roadmap_1166_li
Support native XML data type - see http://en.wikipedia.org/wiki/SQL/XML
@roadmap_1168_li
@roadmap_1167_li
Support triggers with a string property or option: SpringTrigger, OSGITrigger
@roadmap_1169_li
@roadmap_1168_li
MySQL compatibility: update test1 t1, test2 t2 set t1.id = t2.id where t1.id = t2.id;
@roadmap_1170_li
@roadmap_1169_li
Ability to resize the cache array when resizing the cache
@roadmap_1171_li
@roadmap_1170_li
Time based cache writing (one second after writing the log)
@roadmap_1172_li
@roadmap_1171_li
Check state of H2 driver for DDLUtils: https://issues.apache.org/jira/browse/DDLUTILS-185
@roadmap_1173_li
@roadmap_1172_li
Index usage for REGEXP LIKE.
@roadmap_1174_li
@roadmap_1173_li
Compatibility: add a role DBA (like ADMIN).
@roadmap_1175_li
@roadmap_1174_li
Better support multiple processors for in-memory databases.
@roadmap_1176_li
@roadmap_1175_li
Support N'text'
@roadmap_1177_li
@roadmap_1176_li
Support compatibility for jdbc:hsqldb:res:
@roadmap_1178_li
@roadmap_1177_li
HSQLDB compatibility: automatically convert to the next 'higher' data type. Example: cast(2000000000 as int) + cast(2000000000 as int); (HSQLDB: long; PostgreSQL: integer out of range)
@roadmap_1179_li
@roadmap_1178_li
Provide an Java SQL builder with standard and H2 syntax
@roadmap_1180_li
@roadmap_1179_li
Trace: write OS, file system, JVM,... when opening the database
@roadmap_1181_li
@roadmap_1180_li
Support indexes for views (probably requires materialized views)
@roadmap_1182_li
@roadmap_1181_li
Document SET SEARCH_PATH, BEGIN, EXECUTE, parameters
@roadmap_1183_li
@roadmap_1182_li
Server: use one listener (detect if the request comes from an PG or TCP client)
@roadmap_1184_li
@roadmap_1183_li
Optimize SELECT MIN(ID), MAX(ID), COUNT(*) FROM TEST WHERE ID BETWEEN 100 AND 200
DISTINCT: support large result sets by sorting on all columns (additionally) and then removing duplicates.
@roadmap_1187_li
@roadmap_1186_li
Support a special trigger on all tables to allow building a transaction log reader.
@roadmap_1188_li
@roadmap_1187_li
File system with a background writer thread; test if this is faster
@roadmap_1189_li
@roadmap_1188_li
Better document the source code (high level documentation).
@roadmap_1190_li
@roadmap_1189_li
Support select * from dual a left join dual b on b.x=(select max(x) from dual)
@roadmap_1191_li
@roadmap_1190_li
Optimization: don't lock when the database is read-only
@roadmap_1192_li
@roadmap_1191_li
Issue 146: Support merge join.
@roadmap_1193_li
@roadmap_1192_li
Integrate spatial functions from http://geosysin.iict.ch/irstv-trac/wiki/H2spatial/Download
@roadmap_1194_li
@roadmap_1193_li
Cluster: hot deploy (adding a node at runtime).
@roadmap_1195_li
@roadmap_1194_li
Support DatabaseMetaData.insertsAreDetected: updatable result sets should detect inserts.
@roadmap_1196_li
@roadmap_1195_li
Oracle: support DECODE method (convert to CASE WHEN).
@roadmap_1197_li
@roadmap_1196_li
Native search: support "phrase search", wildcard search (* and ?), case-insensitive search, boolean operators, and grouping
@roadmap_1198_li
@roadmap_1197_li
Improve documentation of access rights.
@roadmap_1199_li
@roadmap_1198_li
Support opening a database that is in the classpath, maybe using a new file system. Workaround: detect jar file using getClass().getProtectionDomain().getCodeSource().getLocation().
@roadmap_1200_li
@roadmap_1199_li
Support ENUM data type (see MySQL, PostgreSQL, MS SQL Server, maybe others).
@roadmap_1201_li
@roadmap_1200_li
Remember the user defined data type (domain) of a column.
@roadmap_1202_li
@roadmap_1201_li
MVCC: support multi-threaded kernel with multi-version concurrency.
@roadmap_1203_li
@roadmap_1202_li
Auto-server: add option to define the port range or list.
@roadmap_1204_li
@roadmap_1203_li
Support Jackcess (MS Access databases)
@roadmap_1205_li
@roadmap_1204_li
Built-in methods to write large objects (BLOB and CLOB): FILE_WRITE('test.txt', 'Hello World')
@roadmap_1206_li
@roadmap_1205_li
Improve time to open large databases (see mail 'init time for distributed setup')
@roadmap_1207_li
@roadmap_1206_li
Move Maven 2 repository from hsql.sf.net to h2database.sf.net
Optimize A=? OR B=? to UNION if the cost is lower.
@roadmap_1210_li
@roadmap_1209_li
Javadoc: document design patterns used
@roadmap_1211_li
@roadmap_1210_li
Support custom collators, for example for natural sort (for text that contains numbers).
@roadmap_1212_li
@roadmap_1211_li
Write an article about SQLInjection (h2/src/docsrc/html/images/SQLInjection.txt)
@roadmap_1213_li
@roadmap_1212_li
Convert SQL-injection-2.txt to html document, include SQLInjection.java sample
@roadmap_1214_li
@roadmap_1213_li
Support OUT parameters in user-defined procedures.
@roadmap_1215_li
@roadmap_1214_li
Web site design: http://www.igniterealtime.org/projects/openfire/index.jsp
@roadmap_1216_li
@roadmap_1215_li
HSQLDB compatibility: Openfire server uses: CREATE SCHEMA PUBLIC AUTHORIZATION DBA; CREATE USER SA PASSWORD ""; GRANT DBA TO SA; SET SCHEMA PUBLIC
@roadmap_1217_li
@roadmap_1216_li
Translation: use ?? in help.csv
@roadmap_1218_li
@roadmap_1217_li
Translated .pdf
@roadmap_1219_li
@roadmap_1218_li
Recovery tool: bad blocks should be converted to INSERT INTO SYSTEM_ERRORS(...), and things should go into the .trace.db file
@roadmap_1220_li
@roadmap_1219_li
Issue 357: support getGeneratedKeys to return multiple rows when used with batch updates. This is supported by MySQL, but not Derby. Both PostgreSQL and HSQLDB don't support getGeneratedKeys. Also support it when using INSERT ... SELECT.
@roadmap_1221_li
@roadmap_1220_li
RECOVER=2 to backup the database, run recovery, open the database
@roadmap_1222_li
@roadmap_1221_li
Recovery should work with encrypted databases
@roadmap_1223_li
@roadmap_1222_li
Corruption: new error code, add help
@roadmap_1224_li
@roadmap_1223_li
Space reuse: after init, scan all storages and free those that don't belong to a live database object
@roadmap_1225_li
@roadmap_1224_li
Access rights: add missing features (users should be 'owner' of objects; missing rights for sequences; dropping objects)
@roadmap_1226_li
@roadmap_1225_li
Support NOCACHE table option (Oracle).
@roadmap_1227_li
@roadmap_1226_li
Support table partitioning.
@roadmap_1228_li
@roadmap_1227_li
Add regular javadocs (using the default doclet, but another css) to the homepage.
@roadmap_1229_li
@roadmap_1228_li
The database should be kept open for a longer time when using the server mode.
@roadmap_1230_li
@roadmap_1229_li
Javadocs: for each tool, add a copy & paste sample in the class level.
@roadmap_1231_li
@roadmap_1230_li
Javadocs: add @author tags.
@roadmap_1232_li
@roadmap_1231_li
Fluent API for tools: Server.createTcpServer().setPort(9081).setPassword(password).start();
@roadmap_1233_li
@roadmap_1232_li
MySQL compatibility: real SQL statement for DESCRIBE TEST
@roadmap_1234_li
@roadmap_1233_li
Use a default delay of 1 second before closing a database.
@roadmap_1235_li
@roadmap_1234_li
Write (log) to system table before adding to internal data structures.
@roadmap_1236_li
@roadmap_1235_li
Support direct lookup for MIN and MAX when using WHERE (see todo.txt / Direct Lookup).
@roadmap_1237_li
@roadmap_1236_li
Support other array types (String[], double[]) in PreparedStatement.setObject(int, Object) (with test case).
@roadmap_1238_li
@roadmap_1237_li
MVCC should not be memory bound (uncommitted data is kept in memory in the delta index; maybe using a regular b-tree index solves the problem).
@roadmap_1239_li
@roadmap_1238_li
Oracle compatibility: support NLS_DATE_FORMAT.
@roadmap_1240_li
@roadmap_1239_li
Support for Thread.interrupt to cancel running statements.
@roadmap_1241_li
@roadmap_1240_li
Cluster: add feature to make sure cluster nodes can not get out of sync (for example by stopping one process).
@roadmap_1242_li
@roadmap_1241_li
H2 Console: support CLOB/BLOB download using a link.
@roadmap_1243_li
@roadmap_1242_li
Support flashback queries as in Oracle.
@roadmap_1244_li
@roadmap_1243_li
Import / Export of fixed with text files.
@roadmap_1245_li
@roadmap_1244_li
HSQLDB compatibility: automatic data type for SUM if value is the value is too big (by default use the same type as the data).
@roadmap_1246_li
@roadmap_1245_li
Improve the optimizer to select the right index for special cases: where id between 2 and 4 and booleanColumn
@roadmap_1247_li
@roadmap_1246_li
Linked tables: make hidden columns available (Oracle: rowid and ora_rowscn columns).
@roadmap_1248_li
@roadmap_1247_li
H2 Console: in-place autocomplete.
@roadmap_1249_li
@roadmap_1248_li
Support large databases: split database files to multiple directories / disks (similar to tablespaces).
@roadmap_1250_li
@roadmap_1249_li
H2 Console: support configuration option for fixed width (monospace) font.
@roadmap_1251_li
@roadmap_1250_li
Native fulltext search: support analyzers (specially for Chinese, Japanese).
@roadmap_1252_li
@roadmap_1251_li
Automatically compact databases from time to time (as a background process).
@roadmap_1253_li
@roadmap_1252_li
Test Eclipse DTP.
@roadmap_1254_li
@roadmap_1253_li
H2 Console: autocomplete: keep the previous setting
@roadmap_1255_li
@roadmap_1254_li
executeBatch: option to stop at the first failed statement.
@roadmap_1256_li
@roadmap_1255_li
Implement OLAP features as described here: http://www.devx.com/getHelpOn/10MinuteSolution/16573/0/page/5
@roadmap_1257_li
@roadmap_1256_li
Support Oracle ROWID (unique identifier for each row).
@roadmap_1258_li
@roadmap_1257_li
MySQL compatibility: alter table add index i(c), add constraint c foreign key(c) references t(c);
@roadmap_1259_li
@roadmap_1258_li
Server mode: improve performance for batch updates.
@roadmap_1260_li
@roadmap_1259_li
Applets: support read-only databases in a zip file (accessed as a resource).
@roadmap_1261_li
@roadmap_1260_li
Long running queries / errors / trace system table.
@roadmap_1262_li
@roadmap_1261_li
H2 Console should support JaQu directly.
@roadmap_1263_li
@roadmap_1262_li
Better document FTL_SEARCH, FTL_SEARCH_DATA.
@roadmap_1264_li
@roadmap_1263_li
Sequences: CURRVAL should be session specific. Compatibility with PostgreSQL.
@roadmap_1265_li
@roadmap_1264_li
Index creation using deterministic functions.
@roadmap_1266_li
@roadmap_1265_li
ANALYZE: for unique indexes that allow null, count the number of null.
@roadmap_1267_li
@roadmap_1266_li
MySQL compatibility: multi-table delete: DELETE .. FROM .. [,...] USING - See http://dev.mysql.com/doc/refman/5.0/en/delete.html
@roadmap_1268_li
@roadmap_1267_li
AUTO_SERVER: support changing IP addresses (disable a network while the database is open).
@roadmap_1269_li
@roadmap_1268_li
Avoid using java.util.Calendar internally because it's slow, complicated, and buggy.
@roadmap_1270_li
@roadmap_1269_li
Support TRUNCATE .. CASCADE like PostgreSQL.
@roadmap_1271_li
@roadmap_1270_li
Fulltext search: lazy result generation using SimpleRowSource.
@roadmap_1272_li
@roadmap_1271_li
Fulltext search: support alternative syntax: WHERE FTL_CONTAINS(name, 'hello').
@roadmap_1273_li
@roadmap_1272_li
MySQL compatibility: support REPLACE, see http://dev.mysql.com/doc/refman/6.0/en/replace.html and issue 73.
@roadmap_1274_li
@roadmap_1273_li
MySQL compatibility: support INSERT INTO table SET column1 = value1, column2 = value2
@roadmap_1275_li
@roadmap_1274_li
Docs: add a one line description for each functions and SQL statements at the top (in the link section).
@roadmap_1276_li
@roadmap_1275_li
Javadoc search: weight for titles should be higher ('random' should list Functions as the best match).
@roadmap_1277_li
@roadmap_1276_li
Replace information_schema tables with regular tables that are automatically re-built when needed. Use indexes.
@roadmap_1278_li
@roadmap_1277_li
Issue 50: Oracle compatibility: support calling 0-parameters functions without parenthesis. Make constants obsolete.
@roadmap_1279_li
@roadmap_1278_li
MySQL, HSQLDB compatibility: support where 'a'=1 (not supported by Derby, PostgreSQL)
@roadmap_1280_li
@roadmap_1279_li
Support a data type "timestamp with timezone" using java.util.Calendar.
@roadmap_1281_li
@roadmap_1280_li
Finer granularity for SLF4J trace - See http://code.google.com/p/h2database/issues/detail?id=62
@roadmap_1282_li
@roadmap_1281_li
Add database creation date and time to the database.
@roadmap_1283_li
@roadmap_1282_li
Support ASSERTION.
@roadmap_1284_li
@roadmap_1283_li
MySQL compatibility: support comparing 1='a'
@roadmap_1285_li
@roadmap_1284_li
Support PostgreSQL lock modes: http://www.postgresql.org/docs/8.3/static/explicit-locking.html
@roadmap_1286_li
@roadmap_1285_li
PostgreSQL compatibility: test DbVisualizer and Squirrel SQL using a new PostgreSQL JDBC driver.
@roadmap_1287_li
@roadmap_1286_li
RunScript should be able to read from system in (or quite mode for Shell).
@roadmap_1288_li
@roadmap_1287_li
Natural join: support select x from dual natural join dual.
@roadmap_1289_li
@roadmap_1288_li
Support using system properties in database URLs (may be a security problem).
@roadmap_1290_li
@roadmap_1289_li
Natural join: somehow support this: select a.x, b.x, x from dual a natural join dual b
@roadmap_1291_li
@roadmap_1290_li
Use the Java service provider mechanism to register file systems and function libraries.
@roadmap_1292_li
@roadmap_1291_li
MySQL compatibility: for auto_increment columns, convert 0 to next value (as when inserting NULL).
@roadmap_1293_li
@roadmap_1292_li
Optimization for multi-column IN: use an index if possible. Example: (A, B) IN((1, 2), (2, 3)).
@roadmap_1294_li
@roadmap_1293_li
Optimization for EXISTS: convert to inner join or IN(..) if possible.
@roadmap_1295_li
@roadmap_1294_li
Functions: support hashcode(value); cryptographic and fast
@roadmap_1296_li
@roadmap_1295_li
Serialized file lock: support long running queries.
@roadmap_1297_li
@roadmap_1296_li
Network: use 127.0.0.1 if other addresses don't work.
@roadmap_1298_li
@roadmap_1297_li
Pluggable network protocol (currently Socket/ServerSocket over TCP/IP) - see also TransportServer with master slave replication.
@roadmap_1299_li
@roadmap_1298_li
Support reading JCR data: one table per node type; query table; cache option
@roadmap_1300_li
@roadmap_1299_li
OSGi: create a sample application, test, document.
@roadmap_1301_li
@roadmap_1300_li
help.csv: use complete examples for functions; run as test case.
@roadmap_1302_li
@roadmap_1301_li
Functions to calculate the memory and disk space usage of a table, a row, or a value.
@roadmap_1303_li
@roadmap_1302_li
Re-implement PooledConnection; use a lightweight connection object.
@roadmap_1304_li
@roadmap_1303_li
Doclet: convert tests in javadocs to a java class.
@roadmap_1305_li
@roadmap_1304_li
Doclet: format fields like methods, but support sorting by name and value.
@roadmap_1306_li
@roadmap_1305_li
Doclet: shrink the html files.
@roadmap_1307_li
@roadmap_1306_li
MySQL compatibility: support SET NAMES 'latin1' - See also http://code.google.com/p/h2database/issues/detail?id=56
@roadmap_1308_li
@roadmap_1307_li
Allow to scan index backwards starting with a value (to better support ORDER BY DESC).
@roadmap_1309_li
@roadmap_1308_li
Java Service Wrapper: try http://yajsw.sourceforge.net/
@roadmap_1310_li
@roadmap_1309_li
Batch parameter for INSERT, UPDATE, and DELETE, and commit after each batch. See also MySQL DELETE.
@roadmap_1311_li
@roadmap_1310_li
MySQL compatibility: support ALTER TABLE .. MODIFY COLUMN.
@roadmap_1312_li
@roadmap_1311_li
Use a lazy and auto-close input stream (open resource when reading, close on eof).
Improve SQL documentation, see http://www.w3schools.com/sql/
@roadmap_1316_li
@roadmap_1315_li
MySQL compatibility: DatabaseMetaData.stores*() methods should return the same values. Test with SquirrelSQL.
@roadmap_1317_li
@roadmap_1316_li
MS SQL Server compatibility: support DATEPART syntax.
@roadmap_1318_li
@roadmap_1317_li
Sybase/DB2/Oracle compatibility: support out parameters in stored procedures - See http://code.google.com/p/h2database/issues/detail?id=83
@roadmap_1319_li
@roadmap_1318_li
Support INTERVAL data type (see Oracle and others).
@roadmap_1320_li
@roadmap_1319_li
Combine Server and Console tool (only keep Server).
@roadmap_1321_li
@roadmap_1320_li
Store the Lucene index in the database itself.
@roadmap_1322_li
@roadmap_1321_li
Support standard MERGE statement: http://en.wikipedia.org/wiki/Merge_%28SQL%29
@roadmap_1323_li
@roadmap_1322_li
Oracle compatibility: support DECODE(x, ...).
@roadmap_1324_li
@roadmap_1323_li
MVCC: compare concurrent update behavior with PostgreSQL and Oracle.
@roadmap_1325_li
@roadmap_1324_li
HSQLDB compatibility: CREATE FUNCTION (maybe using a Function interface).
@roadmap_1326_li
@roadmap_1325_li
HSQLDB compatibility: support CALL "java.lang.Math.sqrt"(2.0)
@roadmap_1327_li
@roadmap_1326_li
Support comma as the decimal separator in the CSV tool.
@roadmap_1328_li
@roadmap_1327_li
Compatibility: Java functions with SQLJ Part1 http://www.acm.org/sigmod/record/issues/9912/standards.pdf.gz
@roadmap_1329_li
@roadmap_1328_li
Compatibility: Java functions with SQL/PSM (Persistent Stored Modules) - need to find the documentation.
@roadmap_1330_li
@roadmap_1329_li
CACHE_SIZE: automatically use a fraction of Runtime.maxMemory - maybe automatically the second level cache.
@roadmap_1331_li
@roadmap_1330_li
Support date/time/timestamp as documented in http://en.wikipedia.org/wiki/ISO_8601
@roadmap_1332_li
@roadmap_1331_li
PostgreSQL compatibility: when in PG mode, treat BYTEA data like PG.
@roadmap_1333_li
@roadmap_1332_li
Support =ANY(array) as in PostgreSQL. See also http://www.postgresql.org/docs/8.0/interactive/arrays.html
@roadmap_1334_li
@roadmap_1333_li
IBM DB2 compatibility: support PREVIOUS VALUE FOR sequence.
@roadmap_1335_li
@roadmap_1334_li
Compatibility: use different LIKE ESCAPE characters depending on the mode (disable for Derby, HSQLDB, DB2, Oracle, MSSQLServer).
@roadmap_1336_li
@roadmap_1335_li
Oracle compatibility: support CREATE SYNONYM table FOR schema.table.
@roadmap_1337_li
@roadmap_1336_li
FTP: document the server, including -ftpTask option to execute / kill remote processes
@roadmap_1338_li
@roadmap_1337_li
FTP: problems with multithreading?
@roadmap_1339_li
@roadmap_1338_li
FTP: implement SFTP / FTPS
@roadmap_1340_li
@roadmap_1339_li
FTP: access to a database (.csv for a table, a directory for a schema, a file for a lob, a script.sql file).
@roadmap_1341_li
@roadmap_1340_li
More secure default configuration if remote access is enabled.
@roadmap_1342_li
@roadmap_1341_li
Improve database file locking (maybe use native file locking). The current approach seems to be problematic if the file system is on a remote share (see Google Group 'Lock file modification time is in the future').
@roadmap_1343_li
@roadmap_1342_li
Document internal features such as BELONGS_TO_TABLE, NULL_TO_DEFAULT, SEQUENCE.
@roadmap_1344_li
@roadmap_1343_li
Issue 107: Prefer using the ORDER BY index if LIMIT is used.
@roadmap_1345_li
@roadmap_1344_li
An index on (id, name) should be used for a query: select * from t where s=? order by i
@roadmap_1346_li
@roadmap_1345_li
Support reading sequences using DatabaseMetaData.getTables(null, null, null, new String[]{"SEQUENCE"}). See PostgreSQL.
@roadmap_1347_li
@roadmap_1346_li
Add option to enable TCP_NODELAY using Socket.setTcpNoDelay(true).
@roadmap_1348_li
@roadmap_1347_li
Maybe disallow = within database names (jdbc:h2:mem:MODE=DB2 means database name MODE=DB2).
@roadmap_1349_li
@roadmap_1348_li
Fast alter table add column.
@roadmap_1350_li
@roadmap_1349_li
Improve concurrency for in-memory database operations.
@roadmap_1351_li
@roadmap_1350_li
Issue 122: Support for connection aliases for remote tcp connections.
@roadmap_1352_li
@roadmap_1351_li
Fast scrambling (strong encryption doesn't help if the password is included in the application).
@roadmap_1353_li
@roadmap_1352_li
H2 Console: support -webPassword to require a password to access preferences or shutdown.
@roadmap_1354_li
@roadmap_1353_li
Issue 126: The index name should be "IDX_" plus the constraint name unless there is a conflict, in which case append a number.
@roadmap_1355_li
@roadmap_1354_li
Issue 127: Support activation/deactivation of triggers
@roadmap_1356_li
@roadmap_1355_li
Issue 130: Custom log event listeners
@roadmap_1357_li
@roadmap_1356_li
Issue 131: IBM DB2 compatibility: sysibm.sysdummy1
@roadmap_1358_li
@roadmap_1357_li
Issue 132: Use Java enum trigger type.
@roadmap_1359_li
@roadmap_1358_li
Issue 134: IBM DB2 compatibility: session global variables.
@roadmap_1360_li
@roadmap_1359_li
Cluster: support load balance with values for each server / auto detect.
@roadmap_1361_li
@roadmap_1360_li
FTL_SET_OPTION(keyString, valueString) with key stopWords at first.
@roadmap_1362_li
@roadmap_1361_li
Pluggable access control mechanism.
@roadmap_1363_li
@roadmap_1362_li
Fulltext search (Lucene): support streaming CLOB data.
@roadmap_1364_li
@roadmap_1363_li
Document/example how to create and read an encrypted script file.
@roadmap_1365_li
@roadmap_1364_li
Check state of https://issues.apache.org/jira/browse/OPENJPA-1367 (H2 does support cross joins).
@roadmap_1366_li
@roadmap_1365_li
Fulltext search (Lucene): only prefix column names with _ if they already start with _. Instead of DATA / QUERY / modified use _DATA, _QUERY, _MODIFIED if possible.
@roadmap_1367_li
@roadmap_1366_li
Support a way to create or read compressed encrypted script files using an API.
@roadmap_1368_li
@roadmap_1367_li
Scripting language support (Javascript).
@roadmap_1369_li
@roadmap_1368_li
The network client should better detect if the server is not an H2 server and fail early.
@roadmap_1370_li
@roadmap_1369_li
H2 Console: support CLOB/BLOB upload.
@roadmap_1371_li
@roadmap_1370_li
Database file lock: detect hibernate / standby / very slow threads (compare system time).
@roadmap_1372_li
@roadmap_1371_li
Automatic detection of redundant indexes.
@roadmap_1373_li
@roadmap_1372_li
Maybe reject join without "on" (except natural join).
@roadmap_1374_li
@roadmap_1373_li
Implement GiST (Generalized Search Tree for Secondary Storage).
@roadmap_1375_li
@roadmap_1374_li
Function to read a number of bytes/characters from an BLOB or CLOB.
@roadmap_1376_li
@roadmap_1375_li
Issue 156: Support SELECT ? UNION SELECT ?.
@roadmap_1377_li
@roadmap_1376_li
Automatic mixed mode: support a port range list (to avoid firewall problems).
@roadmap_1378_li
@roadmap_1377_li
Support the pseudo column rowid, oid, _rowid_.
@roadmap_1379_li
@roadmap_1378_li
H2 Console / large result sets: stream early instead of keeping a whole result in-memory
@roadmap_1380_li
@roadmap_1379_li
Support TRUNCATE for linked tables.
@roadmap_1381_li
@roadmap_1380_li
UNION: evaluate INTERSECT before UNION (like most other database except Oracle).
@roadmap_1382_li
@roadmap_1381_li
Delay creating the information schema, and share metadata columns.
@roadmap_1383_li
@roadmap_1382_li
TCP Server: use a nonce (number used once) to protect unencrypted channels against replay attacks.
@roadmap_1384_li
@roadmap_1383_li
Simplify running scripts and recovery: CREATE FORCE USER (overwrites an existing user).
@roadmap_1385_li
@roadmap_1384_li
Support CREATE DATABASE LINK (a custom JDBC driver is already supported).
@roadmap_1386_li
@roadmap_1385_li
Support large GROUP BY operations. Issue 216.
@roadmap_1387_li
@roadmap_1386_li
Issue 163: Allow to create foreign keys on metadata types.
@roadmap_1388_li
@roadmap_1387_li
Logback: write a native DBAppender.
@roadmap_1389_li
@roadmap_1388_li
Cache size: don't use more cache than what is available.
@roadmap_1390_li
@roadmap_1389_li
Allow to defragment at runtime (similar to SHUTDOWN DEFRAG) in a background thread.
@roadmap_1391_li
@roadmap_1390_li
Tree index: Instead of an AVL tree, use a general balanced trees or a scapegoat tree.
@roadmap_1392_li
@roadmap_1391_li
User defined functions: allow to store the bytecode (of just the class, or the jar file of the extension) in the database.
@roadmap_1393_li
@roadmap_1392_li
Compatibility: ResultSet.getObject() on a CLOB (TEXT) should return String for PostgreSQL and MySQL.
@roadmap_1394_li
@roadmap_1393_li
Optimizer: WHERE X=? AND Y IN(?), it always uses the index on Y. Should be cost based.
@roadmap_1395_li
@roadmap_1394_li
Common Table Expression (CTE) / recursive queries: support parameters. Issue 314.
@roadmap_1396_li
@roadmap_1395_li
Oracle compatibility: support INSERT ALL.
@roadmap_1397_li
@roadmap_1396_li
Issue 178: Optimizer: index usage when both ascending and descending indexes are available.
@roadmap_1398_li
@roadmap_1397_li
Issue 179: Related subqueries in HAVING clause.
@roadmap_1399_li
@roadmap_1398_li
IBM DB2 compatibility: NOT NULL WITH DEFAULT. Similar to MySQL Mode.convertInsertNullToZero.
@roadmap_1400_li
@roadmap_1399_li
Creating primary key: always create a constraint.
@roadmap_1401_li
@roadmap_1400_li
Maybe use a different page layout: keep the data at the head of the page, and ignore the tail (don't store / read it). This may increase write / read performance depending on the file system.
@roadmap_1402_li
@roadmap_1401_li
Indexes of temporary tables are currently kept in-memory. Is this how it should be?
@roadmap_1403_li
@roadmap_1402_li
The Shell tool should support the same built-in commands as the H2 Console.
@roadmap_1404_li
@roadmap_1403_li
Maybe use PhantomReference instead of finalize.
@roadmap_1405_li
@roadmap_1404_li
Database file name suffix: should only have one dot by default. Example: .h2db
@roadmap_1406_li
@roadmap_1405_li
Issue 196: Function based indexes
@roadmap_1407_li
@roadmap_1406_li
ALTER TABLE ... ADD COLUMN IF NOT EXISTS columnName.
@roadmap_1408_li
@roadmap_1407_li
Fix the disk space leak (killing the process at the exact right moment will increase the disk space usage; this space is not re-used). See TestDiskSpaceLeak.java
@roadmap_1409_li
@roadmap_1408_li
ROWNUM: Oracle compatibility when used within a subquery. Issue 198.
@roadmap_1410_li
@roadmap_1409_li
Allow to access the database over HTTP (possibly using port 80) and a servlet in a REST way.
@roadmap_1411_li
@roadmap_1410_li
ODBC: encrypted databases are not supported because the ;CIPHER= can not be set.
@roadmap_1412_li
@roadmap_1411_li
Support CLOB and BLOB update, specially conn.createBlob().setBinaryStream(1);
@roadmap_1413_li
@roadmap_1412_li
Optimizer: index usage when both ascending and descending indexes are available. Issue 178.
@roadmap_1414_li
@roadmap_1413_li
Issue 306: Support schema specific domains.
@roadmap_1415_li
@roadmap_1414_li
Triggers: support user defined execution order. Oracle: CREATE OR REPLACE TRIGGER TEST_2 BEFORE INSERT ON TEST FOR EACH ROW FOLLOWS TEST_1. SQL specifies that multiple triggers should be fired in time-of-creation order. PostgreSQL uses name order, which was judged to be more convenient. Derby: triggers are fired in the order in which they were created.
@roadmap_1416_li
@roadmap_1415_li
PostgreSQL compatibility: combine "users" and "roles". See: http://www.postgresql.org/docs/8.1/interactive/user-manag.html
@roadmap_1417_li
@roadmap_1416_li
Improve documentation of system properties: only list the property names, default values, and description.
@roadmap_1418_li
@roadmap_1417_li
Support running totals / cumulative sum using SUM(..) OVER(..).
@roadmap_1419_li
@roadmap_1418_li
Improve object memory size calculation. Use constants for known VMs, or use reflection to call java.lang.instrument.Instrumentation.getObjectSize(Object objectToSize)
@roadmap_1420_li
@roadmap_1419_li
Triggers: NOT NULL checks should be done after running triggers (Oracle behavior, maybe others).
@roadmap_1421_li
@roadmap_1420_li
Common Table Expression (CTE) / recursive queries: support INSERT INTO ... SELECT ... Issue 219.
@roadmap_1422_li
@roadmap_1421_li
Common Table Expression (CTE) / recursive queries: support non-recursive queries. Issue 217.
Common Table Expression (CTE) / recursive queries: support multiple named queries. Issue 220.
@roadmap_1425_li
@roadmap_1424_li
Common Table Expression (CTE) / recursive queries: identifier scope may be incorrect. Issue 222.
@roadmap_1426_li
@roadmap_1425_li
Log long running transactions (similar to long running statements).
@roadmap_1427_li
@roadmap_1426_li
Parameter data type is data type of other operand. Issue 205.
@roadmap_1428_li
@roadmap_1427_li
Some combinations of nested join with right outer join are not supported.
@roadmap_1429_li
@roadmap_1428_li
DatabaseEventListener.openConnection(id) and closeConnection(id).
@roadmap_1430_li
@roadmap_1429_li
Listener or authentication module for new connections, or a way to restrict the number of different connections to a tcp server, or to prevent to login with the same username and password from different IPs. Possibly using the DatabaseEventListener API, or a new API.
@roadmap_1431_li
@roadmap_1430_li
Compatibility for data type CHAR (Derby, HSQLDB). Issue 212.
@roadmap_1432_li
@roadmap_1431_li
Compatibility with MySQL TIMESTAMPDIFF. Issue 209.
@roadmap_1433_li
@roadmap_1432_li
Optimizer: use a histogram of the data, specially for non-normal distributions.
@roadmap_1434_li
@roadmap_1433_li
Trigger: allow declaring as source code (like functions).
@roadmap_1435_li
@roadmap_1434_li
User defined aggregate: allow declaring as source code (like functions).
@roadmap_1436_li
@roadmap_1435_li
The error "table not found" is sometimes caused by using the wrong database. Add "(this database is empty)" to the exception message if applicable.
@roadmap_1437_li
@roadmap_1436_li
MySQL + PostgreSQL compatibility: support string literal escape with \n.
@roadmap_1438_li
@roadmap_1437_li
PostgreSQL compatibility: support string literal escape with double \\.
@roadmap_1439_li
@roadmap_1438_li
Document the TCP server "management_db". Maybe include the IP address of the client.
@roadmap_1440_li
@roadmap_1439_li
Use javax.tools.JavaCompilerTool instead of com.sun.tools.javac.Main
@roadmap_1441_li
@roadmap_1440_li
If a database object was not found in the current schema, but one with the same name existed in another schema, included that in the error message.
@roadmap_1442_li
@roadmap_1441_li
Optimization to use an index for OR when using multiple keys: where (key1 = ? and key2 = ?) OR (key1 = ? and key2 = ?)
@roadmap_1443_li
@roadmap_1442_li
Issue 302: Support optimizing queries with both inner and outer joins, as in: select * from test a inner join test b on a.id=b.id inner join o on o.id=a.id where b.x=1 (the optimizer should swap a and b here). See also TestNestedJoins, tag "swapInnerJoinTables".
@roadmap_1444_li
@roadmap_1443_li
JaQu should support a DataSource and a way to create a Db object using a Connection (for multi-threaded usage with a connection pool).
@roadmap_1445_li
@roadmap_1444_li
Move table to a different schema (rename table to a different schema), possibly using ALTER TABLE ... SET SCHEMA ...;
@roadmap_1446_li
@roadmap_1445_li
nioMapped file system: automatically fall back to regular (non mapped) IO if there is a problem (out of memory exception for example).
@roadmap_1447_li
@roadmap_1446_li
Column as parameter of function table. Issue 228.
@roadmap_1448_li
@roadmap_1447_li
Connection pool: detect ;AUTOCOMMIT=FALSE in the database URL, and if set, disable autocommit for all connections.
@roadmap_1449_li
@roadmap_1448_li
Compatibility with MS Access: support "&" to concatenate text.
@roadmap_1450_li
@roadmap_1449_li
The BACKUP statement should not synchronize on the database, and therefore should not block other users.
@roadmap_1451_li
@roadmap_1450_li
Document the database file format.
@roadmap_1452_li
@roadmap_1451_li
Support reading LOBs.
@roadmap_1453_li
@roadmap_1452_li
Require appending DANGEROUS=TRUE when using certain dangerous settings such as LOG=0, LOG=1, LOCK_MODE=0, disabling FILE_LOCK,...
@roadmap_1454_li
@roadmap_1453_li
Support UDT (user defined types) similar to how Apache Derby supports it: check constraint, allow to use it in Java functions as parameters (return values already seem to work).
@roadmap_1455_li
@roadmap_1454_li
Encrypted file system (use cipher text stealing so file length doesn't need to decrypt; 4 KB header per file, optional compatibility with current encrypted database files).
@roadmap_1456_li
@roadmap_1455_li
Issue 229: SELECT with simple OR tests uses tableScan when it could use indexes.
@roadmap_1457_li
@roadmap_1456_li
GROUP BY queries should use a temporary table if there are too many rows.
@roadmap_1458_li
@roadmap_1457_li
BLOB: support random access when reading.
@roadmap_1459_li
@roadmap_1458_li
CLOB: support random access when reading (this is harder than for BLOB as data is stored in UTF-8 form).
@roadmap_1460_li
@roadmap_1459_li
Compatibility: support SELECT INTO (as an alias for CREATE TABLE ... AS SELECT ...).
@roadmap_1461_li
@roadmap_1460_li
Compatibility with MySQL: support SELECT INTO OUTFILE (cannot be an existing file) as an alias for CSVWRITE(...).
@roadmap_1462_li
@roadmap_1461_li
Compatibility with MySQL: support non-strict mode (sql_mode = "") any data that is too large for the column will just be truncated or set to the default value.
@roadmap_1463_li
@roadmap_1462_li
The full condition should be sent to the linked table, not just the indexed condition. Example: TestLinkedTableFullCondition
@roadmap_1464_li
@roadmap_1463_li
Compatibility with IBM DB2: CREATE PROCEDURE.
@roadmap_1465_li
@roadmap_1464_li
Compatibility with IBM DB2: SQL cursors.
@roadmap_1466_li
@roadmap_1465_li
Single-column primary key values are always stored explicitly. This is not required.
@roadmap_1467_li
@roadmap_1466_li
Compatibility with MySQL: support CREATE TABLE TEST(NAME VARCHAR(255) CHARACTER SET UTF8).
@roadmap_1468_li
@roadmap_1467_li
CALL is incompatible with other databases because it returns a result set, so that CallableStatement.execute() returns true.
@roadmap_1469_li
@roadmap_1468_li
Optimization for large lists for column IN(1, 2, 3, 4,...) - currently an list is used, could potentially use a hash set (maybe only for a part of the values - the ones that can be evaluated).
@roadmap_1470_li
@roadmap_1469_li
Compatibility for ARRAY data type (Oracle: VARRAY(n) of VARCHAR(m); HSQLDB: VARCHAR(n) ARRAY; Postgres: VARCHAR(n)[]).
Issue 297: Oracle compatibility for "at time zone".
@roadmap_1474_li
@roadmap_1473_li
IBM DB2 compatibility: IDENTITY_VAL_LOCAL().
@roadmap_1475_li
@roadmap_1474_li
Support SQL/XML.
@roadmap_1476_li
@roadmap_1475_li
Support concurrent opening of databases.
@roadmap_1477_li
@roadmap_1476_li
Improved error message and diagnostics in case of network configuration problems.
@roadmap_1478_li
@roadmap_1477_li
TRUNCATE should reset the identity columns as in MySQL and MS SQL Server (and possibly other databases).
@roadmap_1479_li
@roadmap_1478_li
Adding a primary key should make the columns 'not null' unless if there is a row with null (compatibility with MySQL, PostgreSQL, HSQLDB; not Derby).
@roadmap_1480_li
@roadmap_1479_li
ARRAY data type: support Integer[] and so on in Java functions (currently only Object[] is supported).
@roadmap_1481_li
@roadmap_1480_li
MySQL compatibility: LOCK TABLES a READ, b READ - see also http://dev.mysql.com/doc/refman/5.0/en/lock-tables.html
@roadmap_1482_li
@roadmap_1481_li
Oracle compatibility: convert empty strings to null. Also convert an empty byte array to null, but not empty varray.
@roadmap_1483_li
@roadmap_1482_li
The HTML to PDF converter should use http://code.google.com/p/wkhtmltopdf/
@roadmap_1484_li
@roadmap_1483_li
Issue 303: automatically convert "X NOT IN(SELECT...)" to "NOT EXISTS(...)".
@roadmap_1485_li
@roadmap_1484_li
MySQL compatibility: update test1 t1, test2 t2 set t1.name=t2.name where t1.id=t2.id.
@roadmap_1486_li
@roadmap_1485_li
Issue 283: Improve performance of H2 on Android.
@roadmap_1487_li
@roadmap_1486_li
Support INSERT INTO / UPDATE / MERGE ... RETURNING to retrieve the generated key(s).
@roadmap_1488_li
@roadmap_1487_li
Column compression option - see http://groups.google.com/group/h2-database/browse_thread/thread/3e223504e52671fa/243da82244343f5d
@roadmap_1489_li
@roadmap_1488_li
PostgreSQL compatibility: ALTER TABLE ADD combined with adding a foreign key constraint, as in ALTER TABLE FOO ADD COLUMN PARENT BIGINT REFERENCES FOO(ID).
@roadmap_1490_li
@roadmap_1489_li
MS SQL Server compatibility: support @@ROWCOUNT.
@roadmap_1491_li
@roadmap_1490_li
PostgreSQL compatibility: LOG(x) is LOG10(x) and not LN(x).
@roadmap_1492_li
@roadmap_1491_li
Issue 311: Serialized lock mode: executeQuery of write operations fails.
@roadmap_1493_li
@roadmap_1492_li
PostgreSQL compatibility: support PgAdmin III (specially the function current_setting).
@roadmap_1494_li
@roadmap_1493_li
MySQL compatibility: support TIMESTAMPADD.
@roadmap_1495_li
@roadmap_1494_li
Support SELECT ... FOR UPDATE with joins (supported by PostgreSQL, MySQL, and HSQLDB; but not Derby).
@roadmap_1496_li
@roadmap_1495_li
Support SELECT ... FOR UPDATE OF [field-list] (supported by PostgreSQL, MySQL, and HSQLDB; but not Derby).
@roadmap_1497_li
@roadmap_1496_li
Support SELECT ... FOR UPDATE OF [table-list] (supported by PostgreSQL, HSQLDB, Sybase).
@roadmap_1498_li
@roadmap_1497_li
TRANSACTION_ID() for in-memory databases.
@roadmap_1499_li
@roadmap_1498_li
TRANSACTION_ID() should be long (same as HSQLDB and PostgreSQL).
@roadmap_1500_li
@roadmap_1499_li
Support [INNER | OUTER] JOIN USING(column [,...]).
@roadmap_1501_li
@roadmap_1500_li
Support NATURAL [ { LEFT | RIGHT } [ OUTER ] | INNER ] JOIN (Derby, Oracle)
@roadmap_1502_li
@roadmap_1501_li
GROUP BY columnNumber (similar to ORDER BY columnNumber) (MySQL, PostgreSQL, SQLite; not by HSQLDB and Derby).
@roadmap_1503_li
@roadmap_1502_li
Sybase / MS SQL Server compatibility: CONVERT(..) parameters are swapped.
@roadmap_1504_li
@roadmap_1503_li
Index conditions: WHERE AGE>1 should not scan through all rows with AGE=1.
@roadmap_1505_li
@roadmap_1504_li
PHP support: H2 should support PDO, or test with PostgreSQL PDO.
@roadmap_1506_li
@roadmap_1505_li
Outer joins: if no column of the outer join table is referenced, the outer join table could be removed from the query.
@roadmap_1507_li
@roadmap_1506_li
Cluster: allow using auto-increment and identity columns by ensuring executed in lock-step.
@roadmap_1508_li
@roadmap_1507_li
MySQL compatibility: index names only need to be unique for the given table.
@roadmap_1509_li
@roadmap_1508_li
Issue 352: constraints: distinguish between 'no action' and 'restrict'. Currently, only restrict is supported, and 'no action' is internally mapped to 'restrict'. The database meta data returns 'restrict' in all cases.
@roadmap_1510_li
@roadmap_1509_li
Oracle compatibility: support MEDIAN aggregate function.
@roadmap_1511_li
@roadmap_1510_li
Issue 348: Oracle compatibility: division should return a decimal result.
@roadmap_1512_li
@roadmap_1511_li
Read rows on demand: instead of reading the whole row, only read up to that column that is requested. Keep an pointer to the data area and the column id that is already read.
@roadmap_1513_li
@roadmap_1512_li
Long running transactions: log session id when detected.
@roadmap_1514_li
@roadmap_1513_li
Optimization: "select id from test" should use the index on id even without "order by".
@roadmap_1515_li
@roadmap_1514_li
Issue 362: LIMIT support for UPDATE statements (MySQL compatibility).
@roadmap_1516_li
@roadmap_1515_li
Sybase SQL Anywhere compatibility: SELECT TOP ... START AT ...
@roadmap_1517_li
@roadmap_1516_li
Use Java 6 SQLException subclasses.
@roadmap_1518_li
@roadmap_1517_li
Issue 390: RUNSCRIPT FROM '...' CONTINUE_ON_ERROR
@roadmap_1519_li
@roadmap_1518_li
Use Java 6 exceptions: SQLDataException, SQLSyntaxErrorException, SQLTimeoutException,..
@roadmap_1520_li
MySQL compatibility: support REPLACE INTO as an alias for MERGE INTO.
@roadmap_1521_h2
@roadmap_1519_h2
Not Planned
@roadmap_1522_li
@roadmap_1520_li
HSQLDB (did) support this: select id i from test where i<0 (other databases don't). Supporting it may break compatibility.
@roadmap_1523_li
@roadmap_1521_li
String.intern (so that Strings can be compared with ==) will not be used because some VMs have problems when used extensively.
@roadmap_1524_li
@roadmap_1522_li
In prepared statements, identifier names (table names and so on) can not be parameterized. Adding such a feature would complicate the source code without providing reasonable speedup, and would slow down regular prepared statements.
