@@ -482,7 +482,7 @@ See also <a href="build.html#providing_patches">Providing Patches</a>.
<ul>
<li>HSQLDB (did) support this: select id i from test where i<0 (other databases don't). Supporting it may break compatibility.
</li><li>String.intern (so that Strings can be compared with ==) will not be used because some VMs have problems when used extensively.
</li><li>In prepared statements, identifier names (table names and so on) can not be parameterized. Adding such a feature would complicate the souce code without providing reasonable speedup, and would slow down regular prepared statements.
</li><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.
If the database was already closed using SHUTDOWN IMMEDIATELY, closing a second connection could throw a NullPointerException if there was a local temporary table.
There are known errors on rollback when the page store is disabled and at the same time MVCC is used. See http://code.google.com/p/h2database/issues/detail?id=158
@changelog_1003_li
Less classes are loaded when using the database in embedded mode.
The DeleteDbFiles tool deleted all files in the .lob.db directory, even files that didn't belong to the database.
@changelog_1004_li
Nested UNION/INTERSECT queries with brackets could produce the wrong result if used within a subquery. Example: select count(*) from (select 1 union (select 2 intersect select 2)) x;
Automatic conversion of old databases to the page store format failed if the database contained LOB files.
@changelog_1005_li
Comparing an column against a constant expression with a higher precision or length than the column could give wrong results (the expression was truncated before comparing).
Nested subqueries didn't work for INSERT INTO and IN(..). Example: insert into test ((select 1));
@changelog_1006_li
Improved PostgreSQL compatibility (support SHOW DEFAULT_TRANSACTION_ISOLATION).
If the database was already closed using SHUTDOWN IMMEDIATELY, closing a second connection could throw a NullPointerException if there was a local temporary table.
@changelog_1007_li
Documentation: the javadocs for Csv.write and read used the wrong default charset.
Less classes are loaded when using the database in embedded mode.
@changelog_1008_li
MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session could query the table. This is now longer possible.
The information schema tables are only initialized when needed. This reduces memory usage and speeds up creating in-memory databases. Each in-memory database needs about 8 KB of heap memory.
@changelog_1009_li
If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
Nested UNION/INTERSECT queries with brackets could produce the wrong result if used within a subquery. Example: select count(*) from (select 1 union (select 2 intersect select 2)) x;
@changelog_1010_li
Triggers: INSTEAD OF triggers are now supported. Such triggers can be defined on views.
Comparing an column against a constant expression with a higher precision or length than the column could give wrong results (the expression was truncated before comparing).
@changelog_1011_li
MVCC: if the page store is disabled, rollback of multiple rows with the same index key did not work correctly.
Improved PostgreSQL compatibility (support SHOW DEFAULT_TRANSACTION_ISOLATION).
@changelog_1012_li
New system property h2.identifiersToUpper. If set to false, identifiers in SQL statements are case sensitive even if they are not quoted.
Documentation: the javadocs for Csv.write and read used the wrong default charset.
@changelog_1013_li
Slightly improved performance if the table is already locked.
MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session could query the table. This is now longer possible.
@changelog_1014_li
CompressLZF: faster decompression.
If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
@changelog_1015_li
PgServer: the wrong size was sent for VARCHAR data. Thanks again to Sergi Vladykin for the patch.
Triggers: INSTEAD OF triggers are now supported. Such triggers can be defined on views.
@changelog_1016_li
MVCC: if the page store is disabled, rollback of multiple rows with the same index key did not work correctly.
@changelog_1017_li
New system property h2.identifiersToUpper. If set to false, identifiers in SQL statements are case sensitive even if they are not quoted.
@changelog_1018_li
Slightly improved performance if the table is already locked.
@changelog_1019_li
CompressLZF: faster decompression.
@changelog_1020_li
PgServer: the wrong size was sent for VARCHAR data. Thanks again to Sergi Vladykin for the patch.
@changelog_1021_li
Serialized access mode (server-less multi-connection mode): fixed getGeneratedKeys() for sequences.
@changelog_1017_h2
@changelog_1022_h2
Version 1.2.127 (2010-01-15)
@changelog_1018_li
@changelog_1023_li
Serialized access mode (server-less multi-connection mode): sequences did not work as expected (there were gaps in generated values when using multiple connections).
@changelog_1019_li
@changelog_1024_li
Page store: new databases can not be opened with older versions.
@changelog_1020_li
@changelog_1025_li
Page store: adding data to new database is now faster.
@changelog_1021_li
@changelog_1026_li
File system: getting the file name from a path is now faster. This should speed up BLOB and CLOB access.
@changelog_1022_li
@changelog_1027_li
PgServer: incorrect SQL types were returned in result set meta data. Concurrently opening a database could fail (PG catalog initialization was not synchronized). Thanks a lot to Sergi Vladykin for providing the patches!
@changelog_1023_li
@changelog_1028_li
SHOW COLUMNS did not work correctly if there where multiple indexes on the same columns.
@changelog_1024_li
@changelog_1029_li
Page store: the wrong write count was written to the database header. This could cause the server-less multi-connection mode to fail.
@changelog_1025_li
@changelog_1030_li
Result sets larger than 2 GB threw an exception "Negative seek offset". Fixed.
@changelog_1026_li
@changelog_1031_li
If the system property h2.check was set to false, an ArrayIndexOutOfBoundsException could occur.
@changelog_1027_li
@changelog_1032_li
Alter table is now supported even if a table has views defined.
@changelog_1028_li
@changelog_1033_li
Fulltext search: exceptions within the fulltext search package had the wrong SQL state.
@changelog_1029_li
@changelog_1034_li
The Lucene fulltext search ignored transaction rollback. Fixed using a trigger on rollback.
@changelog_1030_li
@changelog_1035_li
Trigger can now be called on rollback.
@changelog_1031_li
@changelog_1036_li
The shell script h2.sh ignored command line line arguments.
@changelog_1032_li
@changelog_1037_li
When running H2 in the Google AppEngine for Java, a AccessControlException could be thrown when trying to open a read-only database. Fixed.
@changelog_1033_li
@changelog_1038_li
The user home directory prefix (~) is now only expanded when followed by a slash or backslash, or standing alone.
@changelog_1034_li
@changelog_1039_li
Native fulltext search: before inserting or deleting data, FT_INIT() had to be called. This is no longer required.
@changelog_1035_li
@changelog_1040_li
The .trace.db file is now only created if required.
@changelog_1036_li
@changelog_1041_li
Shell tool: improved PostgreSQL compatibility.
@changelog_1037_li
@changelog_1042_li
Trying to open a database in read-only mode when a .lock.db file exists will now fail with a nice error message.
@changelog_1038_li
@changelog_1043_li
H2 Console: data that is too long is now abbreviated as follows: text... (100000 characters). A large binary is abbreviated as follows: abcdef... (100000 bytes).
@changelog_1039_li
@changelog_1044_li
Faster data conversion from BIGINT or INT to DECIMAL.
@changelog_1040_li
@changelog_1045_li
Server-less multi-connection mode: try to delete log files if switching between read/write operations.
@changelog_1041_li
@changelog_1046_li
CompressLZF: Faster decompress and improved javadocs
@changelog_1042_h2
@changelog_1047_h2
Version 1.2.126 (2009-12-18)
@changelog_1043_li
@changelog_1048_li
The ChangeFileEncryption tool will now fail with an exception if the database is still in use. The Backup tool will also fail except when running in quiet mode.
@changelog_1044_li
@changelog_1049_li
CSVREAD: when reading the column names from the CSV file, column names that contain no special characters are considered case insensitive now.
@changelog_1045_li
@changelog_1050_li
Optimization index conditions of the form 'column=NULL' (which is always false; unlike 'column IS NULL').
@changelog_1046_li
@changelog_1051_li
Script command and tool: the primary key constraint is now listed before inserting the data. This will result in a smaller database when using the page store.
@changelog_1047_li
@changelog_1052_li
Statements with IN(SELECT..) conditions could produce the wrong result. Example: index on id, name; query: select * from test where id between 1 and 3 and name in (select 'World').
@changelog_1048_li
@changelog_1053_li
Statements with IN(..) conditions could produce the wrong result when using views or nested select statements. Example: index on id; index on name; query: select * from (select * from test) where id=1 and name in('a', 'b'). select * from (select * from test) where id=1 and name in('Hello', 'World').
@changelog_1049_li
@changelog_1054_li
Page store: a rollback of a relatively large transaction could fail with an ArrayIndexOutOfBoundsException or a 'row not found' exception in the PageBtreeIndex in some cases.
@changelog_1050_li
@changelog_1055_li
JaQu: the decompiler has been improved, and a few test cases already work. It is still incomplete however.
@changelog_1051_li
@changelog_1056_li
LIKE: any letter is now allowed after the escape character (which is still '\' by default). Previously, an exception was thrown (unlike other databases) if it was not the escape character, '_' or '%'. If the escape character appears at the end of the pattern, the result is it is ignored (like PostgreSQL and MS SQL Server).
@changelog_1052_li
@changelog_1057_li
The reserve heap memory is no longer used.
@changelog_1053_li
@changelog_1058_li
Database.checkpoint() could throw a NullPointerException.
@changelog_1054_h2
@changelog_1059_h2
Version 1.2.125 (2009-12-06)
@changelog_1055_li
@changelog_1060_li
Lucene fulltext search: the Lucene field names now match the table column names, except if the column names start with _ (in which case another _ is prepended). Unfortunately this change means existing fulltext indexes need to be re-built.
@changelog_1056_li
@changelog_1061_li
The shell tool now has a very simple statement history.
@changelog_1057_li
@changelog_1062_li
The zip file system implementation now supports the '~' home directory prefix. Example database URL: jdbc:h2:zip:~/test.zip!/test
@changelog_1058_li
@changelog_1063_li
Right outer joins on tables that were already 'inner joined' was processed incorrectly.
@changelog_1059_li
@changelog_1064_li
Temporary files from LOB objects were not deleted early enough when using the server mode.
@changelog_1060_li
@changelog_1065_li
Trying to alter a temporary table threw a strange exception. It is still not possible to do that, but the exception message is better now.
@changelog_1061_li
@changelog_1066_li
When the system property h2.maxMemoryRowsDistinct was set, and using SELECT DISTINCT, the temporary table was not correctly dropped. This could cause problems in recovery when the process was killed.
@changelog_1062_li
@changelog_1067_li
Trigger that are called before a select statement are now supported. This allows to create tables that work like materialized views.
@changelog_1063_li
@changelog_1068_li
Non-row based triggers were called even if the action didn't match the declared action (INSERT triggers were also called when deleting rows). This has been changed. The MERGE statement calls both INSERT and DELETE triggers.
@changelog_1064_li
@changelog_1069_li
Statements with IN(..) conditions could produce the wrong result or a data conversion error (since version 1.2.120). Examples: index on id, name, condition: id=1 and name in('Hello', 'x'); index on id, query: select * from (select * from test) where id=1 and name in('Hello', 'World').
@changelog_1065_li
@changelog_1070_li
The CompressTool was not multithreading safe. Because of this, the following database operations where also not multithreading safe (even when using different databases): the SCRIPT command (only when using compression), the COMPRESS function, and storing CLOB or BLOB data (only when compression is enabled).
@changelog_1066_li
@changelog_1071_li
The compression algorithm "LZF" is now about 33% faster than before when compressing small block (around 2 KB). It is much faster than Deflate, but the compression ratio is lower. Some of the optimizations are from Sam Van Oort, thanks a lot!
@changelog_1067_li
@changelog_1072_li
Compressing large blocks of data didn't work when using the "Deflate" compression algorithm. Compressing a lot of data could run out of heap memory.
@changelog_1068_li
@changelog_1073_li
The test cases don't access the file system directly, this simplifies GAE for Java testing. Thanks to Vince Bonfanti.
@changelog_1069_li
@changelog_1074_li
More bugs in the server-less multi-connection mode have been fixed.
@changelog_1070_li
@changelog_1075_li
When running against an old database, the SCRIPT statement could generate a SQL script that contained duplicate indexes (PRIMARY_KEY_E).
@changelog_1071_li
@changelog_1076_li
JdbcConnectionPool.getConnection() could throw a NullPointerException.
@changelog_1072_li
@changelog_1077_li
User defined functions: the source code is now available using SELECT SOURCE FROM INFORMATION_SCHEMA.FUNCTION_ALIASES.
@changelog_1073_li
@changelog_1078_li
User defined functions with source code didn't work after re-opening the database.
@changelog_1074_li
@changelog_1079_li
The newsfeeds are now Atom 1.0 standard compliant.
@changelog_1075_li
@changelog_1080_li
The database is now closed after an out of memory exception, because the database could get corrupt otherwise.
@changelog_1076_li
@changelog_1081_li
Better error message if both AUTO_SERVER and SERIALIZED parameters are set to TRUE.
@changelog_1077_li
@changelog_1082_li
Drop table did not delete lob files in old file store (not PAGE_STORE).
@changelog_1078_h2
@changelog_1083_h2
Version 1.2.124 (2009-11-20)
@changelog_1079_li
@changelog_1084_li
Clustering: there is now a way to detect which cluster instances are running.
@changelog_1080_li
@changelog_1085_li
ConvertTraceFile: the SQL statement statistics are better formatted (newline are removed).
@changelog_1081_li
@changelog_1086_li
The file lock thread is now stopped when the database is closed.
@changelog_1082_li
@changelog_1087_li
Issue 140: the Script tool now supports writing to a stream.
@changelog_1083_li
@changelog_1088_li
Issue 138: the trace output of Statement.execute(String, int) and executeUpdate was incorrect.
@changelog_1084_li
@changelog_1089_li
Page store: new databases can not be opened with older versions.
@changelog_1085_li
@changelog_1090_li
Page store: multi-column indexes didn't work if the cache was very small.
@changelog_1086_li
@changelog_1091_li
Page store: opening a database could theoretically result in an endless loop.
@changelog_1087_li
@changelog_1092_li
Page store: adding large indexed columns could get very slow.
@changelog_1088_li
@changelog_1093_li
Page store: after a duplicate key exception, an ArrayIndexOutOfBoundsException could be thrown (only for very large rows).
@changelog_1089_li
@changelog_1094_li
Page store: the recover tool sometimes generated a script file that contained duplicate data.
@changelog_1090_li
@changelog_1095_li
Page store: sometimes opening a read-only database failed.
@changelog_1091_li
@changelog_1096_li
Page store: opening a database sometimes failed if large rows where updated, or if a table was truncated before.
@changelog_1092_li
@changelog_1097_li
Page store: when using a very small page size (128 bytes or smaller), writing a large row could result in an endless recursion. This is only a theoretical problem, as the page size is 2 KB.
@changelog_1093_li
@changelog_1098_li
Page store: getting the min value from a descending index with NULL entries could return the wrong result.
@changelog_1094_li
@changelog_1099_li
Page store: improved auto-recovery after power failure.
@changelog_1095_li
@changelog_1100_li
The JDBC client did not detect that it was not talking to an H2 server. This could result in strange exceptions when trying to connect to another kind of server.
@changelog_1096_li
@changelog_1101_li
User defined functions can be created with source code. Example: CREATE ALIAS HI AS 'String hi() { return "Hello"; }'
@changelog_1097_li
@changelog_1102_li
Database file lock: the exception "lock file modified in the future" is no longer thrown; instead, opening the file will be delayed by 2 seconds.
@changelog_1098_li
@changelog_1103_li
Inserting LOBs got slower each time the process was restarted. It could loop endlessly after about 1000 process restarts.
@changelog_1099_li
@changelog_1104_li
Issue 117: Multi-version concurrency: concurrent MERGE statements now work.
@changelog_1100_li
@changelog_1105_li
Improved read-only database detection.
@changelog_1101_h2
@changelog_1106_h2
Version 1.2.123 (2009-11-08)
@changelog_1102_li
@changelog_1107_li
Page store: new databases can not be opened with older versions.
@changelog_1103_li
@changelog_1108_li
Page store: updating large rows (rows with more than 2000 bytes of data) could corrupt the database.
@changelog_1104_li
@changelog_1109_li
Page store: inserting very large rows failed with ArrayIndexOutOfBoundsException.
@changelog_1105_li
@changelog_1110_li
When using multi-threaded kernel mode, setting disabling locking (LOCK_MODE=0) will now throw an exception. At this time this combination will result in corruption when multiple threads try to update the same table.
@changelog_1106_li
@changelog_1111_li
The fulltext search methods and fields are now protected instead of private, to make the classes more easily extensible.
@changelog_1107_li
@changelog_1112_li
The Lucene fulltext search now also returns the score.
@changelog_1108_li
@changelog_1113_li
New function SCOPE_IDENTITY() to avoid problems when inserting rows in a trigger.
@changelog_1109_li
@changelog_1114_li
Statement.getGeneratedKeys() returned the wrong value if a trigger changed the identity value after inserting the row.
@changelog_1110_li
@changelog_1115_li
Improved error messages: identifiers and values are now quoted.
@changelog_1111_li
@changelog_1116_li
Improved error message when casting a value failed: the column name and type is included in the message.
@changelog_1112_li
@changelog_1117_li
Improved support for GAE for Java thanks to Vince Bonfanti.
@changelog_1113_h2
@changelog_1118_h2
Version 1.2.122 (2009-10-28)
@changelog_1114_li
@changelog_1119_li
The native fulltext search now supports streaming CLOB data.
@changelog_1115_li
@changelog_1120_li
If the database URL ends with ;PAGE_STORE=TRUE and a database in the old format exists, it is automatically converted to the new page store format if possible. A backup of the database is created first. Automatic conversion is not supported if the database was not closed normally (if it contains uncommitted transactions).
@changelog_1116_li
@changelog_1121_li
Dropping the current user is now allowed if another admin user exists.
@changelog_1117_li
@changelog_1122_li
Values of type BINARY or BLOB could not be converted to the data type OTHER.
@changelog_1118_li
@changelog_1123_li
SHUTDOWN COMPACT now fully compacts the database.
@changelog_1119_li
@changelog_1124_li
New system properties h2.maxCompactCount and h2.maxCompactTime to allow changing the default behavior (at most 2 seconds compacting when closing the database).
@changelog_1120_li
@changelog_1125_li
New sorted insert optimization (see Performance / Database Performance Tuning).
@changelog_1121_li
@changelog_1126_li
Issue 116: The files h2*-sources.jar and h2*-javadoc.jar are now in the Maven repository.
@changelog_1122_li
@changelog_1127_li
Page store: opening a large database was slow if it was not closed before.
@changelog_1123_li
@changelog_1128_li
Page store: new write and read counters in the meta data table. Use SELECT * FROM INFORMATION_SCHEMA.SETTINGS WHERE NAME IN( 'info.FILE_WRITE_TOTAL', 'info.FILE_WRITE', 'info.FILE_READ', 'info.CACHE_MAX_SIZE', 'info.CACHE_SIZE')
@changelog_1124_li
@changelog_1129_li
The SQL syntax is documented using (railroad) diagrams. The diagrams are HTML.
@changelog_1125_li
@changelog_1130_li
The documentation is no longer available in Japanese because the translation was too much out of sync. Please use the Google translation instead.
@changelog_1126_li
@changelog_1131_li
Certain queries were not sorted if subselect queries were involved
@changelog_1127_li
@changelog_1132_li
More bugs in the server-less multi-connection mode have been fixed: 90097 The database is read only, caches must be cleared on reconnect, etc.
@changelog_1128_h2
@changelog_1133_h2
Version 1.2.121 (2009-10-11)
@changelog_1129_li
@changelog_1134_li
Better support GaeVFS (Google App Engine Virtual File System) thanks to Thanks to Vince Bonfanti.
@changelog_1130_li
@changelog_1135_li
CSVREAD didn't close the file. Thanks to Vince Bonfanti for the patch!
@changelog_1131_li
@changelog_1136_li
If a database in the old format exists, it is now used. The system property is used for new databases, or if databases exist in both formats. In any case, the flag in the URL overrides this logic.
@changelog_1132_li
@changelog_1137_li
Page store bugs were fixed. Large values in indexed columns could corrupt the index.
@changelog_1133_li
@changelog_1138_li
The page store did not work when using Retrotranslator (because the Retrotranslator doesn't support Integer.reverse and Long.reverse).
@changelog_1134_li
@changelog_1139_li
New system property h2.pageStoreTrim to disable shrinking the database when closing (disabled by default, meaning by default the database is trimmed).
@changelog_1135_h2
@changelog_1140_h2
Version 1.2.120 (2009-10-04)
@changelog_1136_li
@changelog_1141_li
This is a beta version.
@changelog_1137_li
@changelog_1142_li
Large updates could throw an ArrayIndexOutOfBoundsException in RowList.writeRow.
@changelog_1138_li
@changelog_1143_li
In version 1.2, the following system properties are now enabled by default: h2.pageStore, h2.nullConcatIsNull, h2.optimizeInList. The default value for h2.defaultMaxLengthInplaceLob is now 4096 (it was 1024 with version 1.1).
@changelog_1139_li
@changelog_1144_li
New databases are now stored in the new 'page store' file format. Existing databases are kept in the old file format. To use the old file format, append ;PAGE_STORE=FALSE to the database URL or set the system property h2.pageStore to false.
@changelog_1140_li
@changelog_1145_li
Issue 125: Renaming primary keys was not persistent. Fixed. Unfortunately, databases created by this version can not be opened with older versions because of this change.
@changelog_1141_li
@changelog_1146_li
Issue 124: Hibernate schema validation failed for decimal/numeric columns. This problem is fixed in the Hibernate dialect that is included with H2 (src/tools/org/hibernate/dialect/H2Dialect.java.txt), but not in Hibernate yet.
@changelog_1142_li
@changelog_1147_li
PostgreSQL compatibility: function LASTVAL() as an alias for IDENTITY().
@changelog_1143_li
@changelog_1148_li
Linked tables now support default values when inserting, updating or merging.
@changelog_1144_li
@changelog_1149_li
Bugfixes in the page store.
@changelog_1145_li
@changelog_1150_li
Possibility to set a vendor id in Constants.java, so that unofficial builds are distinguishable from official releases.
@changelog_1146_li
@changelog_1151_li
Allow writing to linked tables in readonly databases.
@changelog_1147_h2
@changelog_1152_h2
Version 1.1.119 (2009-09-26)
@changelog_1148_li
@changelog_1153_li
SQL statements in the exception message are no longer included if they contain '--hide--'.
@changelog_1149_li
@changelog_1154_li
Temporary local tables did not always work after reconnect if AUTO_SERVER=TRUE
@changelog_1150_li
@changelog_1155_li
New system property h2.defaultMaxLengthInplaceLob to change the default maximum size of an in-place LOB object.
@changelog_1151_li
@changelog_1156_li
New system property h2.nullConcatIsNull to change the default null concatenation behavior. The default will be enabled in version 1.2.
@changelog_1152_li
@changelog_1157_li
The cache algorithm TQ is disabled in this version, because it is unstable, and because the current implementation does not have any measurable advantages over the default.
@changelog_1153_li
@changelog_1158_li
New committer: Christian Peter. He works for <a href="http://www.docware.com">Docware</a> and helped a lot finding and fixing bugs, and generally improving the database. He is now a committer.
@changelog_1154_li
@changelog_1159_li
ChangeFileEncryption did not work with Lob subdirectories. Fixed.
@changelog_1155_li
@changelog_1160_li
Issue 121: JaQu: new simple update and merge methods.
@changelog_1156_li
@changelog_1161_li
Issue 120: JaQu didn't close result sets.
@changelog_1157_li
@changelog_1162_li
Issue 119: JaQu creates wrong WHERE conditions on some inputs.
@changelog_1158_li
@changelog_1163_li
The new page store mechanism is now alpha-level quality. The next release will most likely be "1.2.120 beta" where this mode is enabled by default. To use it right now, append ;PAGE_STORE=TRUE to the database URL. The file format of this mode will probably not change any more.
@changelog_1159_li
@changelog_1164_li
SELECT COUNT(*) FROM SYSTEM_RANGE(...) returned the wrong result. Fixed.
@changelog_1160_li
@changelog_1165_li
The Recover tool now also processes the log files, however applying those changes is still a manual process.
@changelog_1161_li
@changelog_1166_li
New sample application that shows how to pass data to a trigger.
@changelog_1162_li
@changelog_1167_li
More bugs in the server-less multi-connection mode have been fixed: On Windows, two processes could write to the same database at the same time.
@changelog_1163_li
@changelog_1168_li
When loading triggers or other client classes (static functions, database event listener, user aggregate functions, other JDBC drivers), the database now uses the context class loader if the class could not be found using Class.forName().
@changelog_1164_li
@changelog_1169_li
Updating many rows with the same CLOB or BLOB values could result in FileNotFoundException.
@changelog_1165_li
@changelog_1170_li
Statement.getConnection() threw an exception if the connection was already closed.
@changelog_1166_li
@changelog_1171_li
The native fulltext index kept a reference to a database after the database was closed.
@changelog_1167_li
@changelog_1172_li
Non-unique in-memory hash indexes are now supported. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1168_li
@changelog_1173_li
The optimizer does a better job for joins if indexes are missing.
@changelog_1169_h2
@changelog_1174_h2
Version 1.1.118 (2009-09-04)
@changelog_1170_li
@changelog_1175_li
SHOW COLUMNS only listed indexed columns.
@changelog_1171_li
@changelog_1176_li
When calling SHUTDOWN IMMEDIATELY in the server mode, the .trace.db file was not closed.
@changelog_1172_li
@changelog_1177_li
DatabaseMetaData.getPrimaryKeys: the wrong constraint name was reported if there was another constraint on the same table and columns.
@changelog_1173_li
@changelog_1178_li
AUTO_INCREMENT now works in the same way in ALTER TABLE ALTER COLUMN as in CREATE TABLE (it does not create a primary key).
@changelog_1174_li
@changelog_1179_li
Native fulltext search: before searching, FT_INIT() had to be called. This is no longer required.
@changelog_1175_li
@changelog_1180_li
Better support GaeVFS (Google App Engine Virtual File System).
@changelog_1176_li
@changelog_1181_li
JaQu: the plan is to support natural (pure Java / Scala) conditions such as (id == 1 && name.equals("Test")). A proof of concept decompiler is now included (it doesn't work yet).
@changelog_1177_li
@changelog_1182_li
Various bugfixes and improvements in the page store mechanism (still experimental).
@changelog_1178_li
@changelog_1183_li
PreparedStatement.setObject now converts a java.lang.Character to a string.
@changelog_1179_li
@changelog_1184_li
H2 Console: PierPaolo Ucchino has completed the Italian translation. Thanks a lot!
@changelog_1180_li
@changelog_1185_li
Various tools now use Java 5 var-args, such as main the methods and SimpleResultSet.addRow.
@changelog_1181_li
@changelog_1186_li
H2 Console: indexes of tables of non-default schemas are now also listed.
@changelog_1182_li
@changelog_1187_li
Issue 111: Multi-version concurrency / duplicate primary key after rollback.
@changelog_1183_li
@changelog_1188_li
Issue 110: Multi-version concurrency / wrong exception is thrown.
@changelog_1184_li
@changelog_1189_li
Parser: sequenceName.NEXTVAL and CURRVAL did not respect the schema search path.
@changelog_1185_li
@changelog_1190_li
Issue 101: The following sequence could throw the exception "Row not found when trying to delete": start a transaction, insert many rows, delete many rows, rollback. The number of rows depends on the cache size.
@changelog_1186_li
@changelog_1191_li
The stack trace of very common exceptions is no longer written to the .trace.db file by default.
@changelog_1187_li
@changelog_1192_li
An optimization for OR is implemented, but disabled by default. Expressions of the type X=1 OR X=2 are converted to X IN(1, 2). To enable, set the system property h2.optimizeInList to true before loading the H2 JDBC driver.
@changelog_1188_li
@changelog_1193_li
An optimization for IN(..) and IN(SELECT...) is implemented, but disabled by default. To enable, set the system property h2.optimizeInList to true before loading the H2 JDBC driver. If enabled, this overrides h2.optimizeIn and h2.optimizeInJoin. Unlike now, this optimization will also speed up updates and deletes.
@changelog_1189_h2
@changelog_1194_h2
Version 1.1.117 (2009-08-09)
@changelog_1190_li
@changelog_1195_li
New committer: Sam Van Oort has been contributing to H2 since quite some time in many ways (on the mailing list, documentation, and in the form of patches). He is now a committer.
@changelog_1191_li
@changelog_1196_li
JaQu: the order of the fields in the database no longer needs to match the order in the database.
@changelog_1192_li
@changelog_1197_li
Issue 103: MVCC: the setting MAX_MEMORY_UNDO can currently not be supported when using multi-version concurrency, that means the complete undo log must fit in memory.
@changelog_1193_li
@changelog_1198_li
LIKE: the escape mechanism can now be disable using ESCAPE ''. The default escape character can be changed using the system property h2.defaultEscape. The default is still '\' (as in MySQL and PostgreSQL).
@changelog_1194_li
@changelog_1199_li
Views using functions were not re-evaluated when necessary.
@changelog_1195_li
@changelog_1200_li
Improved MySQL compatibility for SHOW COLUMNS.
@changelog_1196_li
@changelog_1201_li
Improved PostgreSQL compatibility for timestamp literals with timezone.
@changelog_1197_li
@changelog_1202_li
Sergi Vladykin translated the error messages to Russian. Thanks a lot!
@changelog_1198_li
@changelog_1203_li
Support for Java 6 DatabaseMetaData.getTables, getColumns, getProcedures, and getProcedureColumns.
@changelog_1199_li
@changelog_1204_li
Issue 101: Rollback of a large transaction (more than 100000 rows) could fail.
@changelog_1200_li
@changelog_1205_li
Various bugfixes and improvements in the page store mechanism (still experimental).
@changelog_1201_li
@changelog_1206_li
The functions LENGTH, OCTET_LENGTH, and BIT_LENGTH now return BIGINT.
@changelog_1202_li
@changelog_1207_li
Data types CLOB and BLOB: the maximum precision was Integer.MAX_VALUE, it is now Long.MAX_VALUE.
@changelog_1203_li
@changelog_1208_li
Multi-threaded kernel: creating and dropping temporary database objects and the potentially free pages list was not correctly synchronized. Thanks a lot to Eric Faulhaber for the test case and patch!
@changelog_1204_li
@changelog_1209_li
Parsing SQL script files is now faster.
@changelog_1205_li
@changelog_1210_li
CSV reading is now faster.
@changelog_1206_li
@changelog_1211_li
SimpleResultSet.newInstance(SimpleRowSource rs) did not work.
@changelog_1207_h2
@changelog_1212_h2
Version 1.1.116 (2009-07-18)
@changelog_1208_li
@changelog_1213_li
Server-less multi-connection mode: more bugs are fixed.
@changelog_1209_li
@changelog_1214_li
The built-in help (INFORMATION_SCHEMA.HELP) is smaller, shrinking the jar file size a bit.
@changelog_1210_li
@changelog_1215_li
H2 Console: column of tables of non-default schemas are now also listed, except for schemas starting with 'INFO'.
@changelog_1211_li
@changelog_1216_li
ALTER TABLE: removing an auto-increment or identity column didn't remove the sequence.
@changelog_1212_li
@changelog_1217_li
Creating indexes is now a bit faster.
@changelog_1213_li
@changelog_1218_li
PG Server: new system property h2.pgClientEncoding to explicitly set the encoding for clients that don't send the encoding (the default encoding is UTF-8). Thanks a lot to Sergi Vladykin for the patch!
@changelog_1214_li
@changelog_1219_li
PG Server: improved compatibility by using the type ids of the PostgreSQL driver. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1215_li
@changelog_1220_li
H2 Console: Oracle system tables are no longer listed, improving performance.
@changelog_1216_li
@changelog_1221_li
Result sets are now read-only except if the statement or prepared statement was created with the concurrency ResultSet.CONCUR_UPDATABLE. This change is required because the old behavior (all result set are updatable) violated the JDBC spec. For backward compatibility, use the system property h2.defaultResultSetConcurrency.
@changelog_1217_li
@changelog_1222_li
New system property h2.defaultResultSetConcurrency to change the default result set concurrency.
@changelog_1218_li
@changelog_1223_li
JDBC: using an invalid result set type or concurrency now throws an exception.
@changelog_1219_li
@changelog_1224_li
If a pooled connection was not closed but garbage collected, a NullPointerException could occur.
@changelog_1220_li
@changelog_1225_li
Fulltext search: a NullPointerException was thrown when updating a value that was NULL previously.
@changelog_1221_li
@changelog_1226_li
The Recover tool did not work with .data.db files of the wrong size.
@changelog_1222_li
@changelog_1227_li
Triggers: if there was an exception when initializing a trigger, this exception could be hidden, and in some cases (specially when using the Lucene fulltext index mechanism) a NullPointerException was thrown later on. Now the exception that occurred on init is thrown when changing data.
@changelog_1223_li
@changelog_1228_li
The soft-references cache (CACHE_TYPE=SOFT_LRU) could throw a NullPointerException.
@changelog_1224_li
@changelog_1229_li
To enable the new page store mechanism, append ;PAGE_STORE=TRUE to the database URL. or set the system property h2.pageStore to true. This mechanism is still experimental, and the file format will change, but it is quite stable now.
@changelog_1225_h2
@changelog_1230_h2
Version 1.1.115 (2009-06-21)
@changelog_1226_li
@changelog_1231_li
The new storage mechanism is now alpha quality. To try it out, set the system property "h2.pageStore" to "true" (java -Dh2.pageStore=true). There are still bugs to be found and fixed, for example inserting many rows references a lot of main memory. Performance is currently about the same as with the regular storage mechanism, but the database file size is smaller. The file format is not stable yet.
@changelog_1227_li
@changelog_1232_li
ALTER TABLE could throw an exception "object already exists" in some cases.
@changelog_1228_li
@changelog_1233_li
Views: in some situations, an ArrayIndexOutOfBoundsException was thrown when using the same view concurrently.
@changelog_1229_li
@changelog_1234_li
java.util.UUID is now supported in PreparedStatement.setObject and user defined Java functions. ResultSet.getObject() returns a java.util.UUID when using the UUID data type.
@changelog_1230_li
@changelog_1235_li
H2 Console: the language was reset to the browser language when disconnecting.
@changelog_1231_li
@changelog_1236_li
H2 Console: improved Polish translation.
@changelog_1232_li
@changelog_1237_li
Server-less multi-connection mode: more bugs are fixed.
@changelog_1233_li
@changelog_1238_li
The download page now included the SHA1 checksums.
@changelog_1234_li
@changelog_1239_li
Shell tool: the file encoding workaround is now documented if you run java org.h2.tools.Shell -?.
@changelog_1235_li
@changelog_1240_li
The RunScript tool and SQL statement did not work with the compression method LZF.
@changelog_1236_li
@changelog_1241_li
Fulltext search: searching for NULL or an empty string threw an exception.
@changelog_1237_li
@changelog_1242_li
Lucene fulltext search: FTL_DROP_ALL did not drop the triggers.
@changelog_1238_li
@changelog_1243_li
Backup: if the database contained CLOB or BLOB data, the backup included a file entry for the LOB directory. This caused the restore to fail.
@changelog_1239_li
@changelog_1244_li
Data types: LONG is now an alias for BIGINT.
@changelog_1240_h2
@changelog_1245_h2
Version 1.1.114 (2009-06-01)
@changelog_1241_li
@changelog_1246_li
ResultSetMetaData.getColumnClassName returned the wrong class for CLOB and BLOB columns.
@changelog_1242_li
@changelog_1247_li
Fulltext search: data is no longer deleted and re-inserted if the indexed columns didn't change.
@changelog_1243_li
@changelog_1248_li
In some situations, an ArrayIndexOutOfBoundsException was thrown when adding rows. This was caused by a bug in the b-tree code.
@changelog_1244_li
@changelog_1249_li
Microsoft Windows Vista: when using the the installer, Vista wrote "This program may not have installed correctly." This message should no longer appear (in the h2.nsi file, the line 'RequestExecutionLevel highest' was added).
@changelog_1245_li
@changelog_1250_li
The Recover tool did not always work when the database contains referential integrity constraints.
@changelog_1246_li
@changelog_1251_li
Java 1.5 is now required to run H2. If required, Retrotranslator can be used to create a Java 1.4 version (http://retrotranslator.sourceforge.net/).
@changelog_1247_h2
@changelog_1252_h2
Version 1.1.113 (2009-05-21)
@changelog_1248_li
@changelog_1253_li
Shell tool: the built-in commands EXIT, HELP, ?, LIST, and so on didn't work with a semicolon at the end.
@changelog_1249_li
@changelog_1254_li
JDK 1.5 is now required to build the jar file. However it is still possible to create a jar file for Java 1.4. For details, see buildRelease.sh and buildRelease.bat. As an alternative, compile using JDK 1.5 or 1.6 and use Retrotranslator to create a Java 1.4 version (http://retrotranslator.sourceforge.net/).
@changelog_1250_li
@changelog_1255_li
When deleting or updating many rows in a table, the space in the index file was not re-used in the default mode (persistent database, b-tree index, LOG=1). This caused the index file to grow over time. Workarounds were to delete and re-created the index file, alter the table (add a remove a column), or append ;LOG=2 to the database URL. To disable the change, set the system property h2.reuseSpaceBtreeIndex to false.
@changelog_1251_li
@changelog_1256_li
Identifiers with a digit and then a dollar sign didn't work. Example: A1$B.
@changelog_1252_li
@changelog_1257_li
MS SQL Server compatibility: support for linked tables with NVARCHAR, NCHAR, NCLOB, and LONGNVARCHAR.
@changelog_1253_li
@changelog_1258_li
Android: workaround for a problem when using read-only databases in zip files (skip seems to be implemented incorrectly on the Android system).
@changelog_1254_li
@changelog_1259_li
Calling execute() or prepareStatement() with null as the SQL statement now throws an exception.
@changelog_1255_li
@changelog_1260_li
Benchmark: the number of executed statements was incorrect. The H2 database was loaded at the beginning of the test to collect results, now it is loaded at the very end. Thanks to Fred Toussi from HSQLDB for reporting those problems. However the changed do not affect the relative performance.
@changelog_1256_li
@changelog_1261_li
H2 Console: command line settings are no longer stored in the properties file. They are now only used for the current process, except if they are explicitly saved.
@changelog_1257_li
@changelog_1262_li
Cache: support for a second level soft-references cache. To enable it, append ;CACHE_TYPE=SOFT_LRU (or SOFT_TQ) to the database URL, or set the system property h2.cacheTypeDefault to "SOFT_LRU" / "SOFT_TQ". Enabling the second level cache reduces performance for small databases, but speeds up large databases. It makes sense to use it if the available memory size is unknown. Thanks a lot to Jan Kotek!
@changelog_1258_h2
@changelog_1263_h2
Version 1.1.112 (2009-05-01)
@changelog_1259_li
@changelog_1264_li
JdbcPreparedStatement.toString() could throw a NullPointerException.
@changelog_1260_li
@changelog_1265_li
EclipseLink: added H2Platform.supportsIdentity().
@changelog_1261_li
@changelog_1266_li
Connection pool: the default login timeout is now 5 minutes.
@changelog_1262_li
@changelog_1267_li
After truncating tables, opening large databases could become slow because indexes were always re-built unnecessarily when opening.
@changelog_1263_li
@changelog_1268_li
More bugs in the server-less multi-connection mode have been fixed: Sometimes parameters of prepared statements were lost when a reconnecting. Concurrent read operations were slow. To improve performance, executeQuery(..) must be used for queries (execute(..) switches to the write mode, which is slow).
@changelog_1264_li
@changelog_1269_li
GROUP BY queries with a self-join (join to the same table) that were grouped by columns with indexes returned the wrong result in some cases.
@changelog_1265_li
@changelog_1270_li
Improved error message when the .lock.db file modification time is in the future.
@changelog_1266_li
@changelog_1271_li
The MERGE statement now returns 0 as the generated key if the row was updated.
@changelog_1267_li
@changelog_1272_li
Running code coverage is now automated.
@changelog_1268_li
@changelog_1273_li
A file system implementation can now be registered using FileSystem.register.
@changelog_1269_li
@changelog_1274_li
The database file system is no longer included in the jar file, it moved to the test section.
@changelog_1270_h2
@changelog_1275_h2
Version 1.1.111 (2009-04-10)
@changelog_1271_li
@changelog_1276_li
In-memory databases can now run inside the Google App Engine.
@changelog_1272_li
@changelog_1277_li
Queries that are ordered by an indexed column returned no rows in certain cases (if all rows were deleted from the table previously, and there is a low number of rows in the table, and when not using other conditions, and when using the default b tree index).
@changelog_1273_li
@changelog_1278_li
The wrong exception was thrown when using unquoted text for the SQL statements COMMENT, ALTER USER, and SET PASSWORD.
@changelog_1274_li
@changelog_1279_li
The built-in connection pool did not roll back transactions and enable autocommit enabled after closing a connection.
@changelog_1275_li
@changelog_1280_li
Sometimes a StackOverflow occurred when checking for deadlock. See also http://code.google.com/p/h2database/issues/detail?id=61
@changelog_1276_li
@changelog_1281_li
The Shell tool no longer truncates results with only one column, and displays a message if data was truncated.
@changelog_1277_h2
@changelog_1282_h2
Version 1.1.110 (2009-04-03)
@changelog_1278_li
@changelog_1283_li
Support for not persistent in-memory tables in regular (persistent) databases using CREATE MEMORY TABLE(..) NOT PERSISTENT. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1279_li
@changelog_1284_li
The H2 Console trimmed the password (removed leading and trailing spaces). This is no longer the case, to support encrypted H2 database with an empty user password.
@changelog_1280_li
@changelog_1285_li
The data type of a SUBSTRING method was wrong.
@changelog_1281_li
@changelog_1286_li
ResultSet.findColumn and get methods with column label parameters now also check for matching column names (like most databases except MySQL).
@changelog_1282_li
@changelog_1287_li
H2 Console: the browser system property now supports a list of arguments. Example: java -Dh2.browser="open,-a,Safari,%url" ...
@changelog_1283_li
@changelog_1288_li
Improved Javadoc navigation (similar to Scaladoc).
@changelog_1284_li
@changelog_1289_li
H2 Console: auto-complete of identifiers did not work correctly for H2 databases in MySQL mode.
@changelog_1285_li
@changelog_1290_li
DISTINCT and GROUP BY on a CLOB column was broken.
@changelog_1286_li
@changelog_1291_li
The FTP server moved to the tools section and is no longer included in the h2*.jar file.
@changelog_1287_li
@changelog_1292_li
Improved error message for unsupported features: now the message says what exactly is not supported.
@changelog_1288_li
@changelog_1293_li
Improved OSGi support.
@changelog_1289_li
@changelog_1294_li
Some internal caches did not use the LRU mechanism. Fixed (LOB file list, optimizer cost cache, trace system, view indexes, collection keys, compressed in-memory file system).
@changelog_1290_li
@changelog_1295_li
The API of the tools changed a bit (each tool now returns an exit code).
@changelog_1291_li
@changelog_1296_li
Command line help of the tools now match the javadocs. The build converts the javadocs to a resource that is read by the tool at runtime. This should not have an effect on using the database, but it reduces duplicate and out-of-sync documentation.
@changelog_1292_li
@changelog_1297_li
CREATE TABLE: improved compatibility (support for UNIQUE NOT NULL).
@changelog_1293_li
@changelog_1298_li
DatabaseMetaData.getSQLKeywords now returns the correct list.
@changelog_1294_li
@changelog_1299_li
Deterministic user defined functions did not work when the parameter was a column. Fixed.
@changelog_1295_li
@changelog_1300_li
JdbcConnectionPool.setLoginTimeout with 0 now uses the default timeout.
@changelog_1296_li
@changelog_1301_li
Creating a JdbcConnectionPool has been simplified a bit.
@changelog_1297_li
@changelog_1302_li
The built-in connection pool did not re-use connections. Getting a connection using the built-in JdbcConnectionPool is now about 70 times faster than opening connections using DriverManager.getConnection.
@changelog_1298_li
@changelog_1303_li
More bugs in the server-less multi-connection mode have been fixed: If a process terminated while writing, other open connections were blocked. If two processes were writing to the database, sometimes the database was corrupt after closing.
@changelog_1299_li
@changelog_1304_li
Linked tables to SQLite database can now be created.
@changelog_1300_li
@changelog_1305_li
Nested IN(IN(...)) didn't work.
@changelog_1301_li
@changelog_1306_li
NIO storage: the nio: prefix was using memory mapped files instead of FileChannel.
@changelog_1302_h2
@changelog_1307_h2
Version 1.1.109 (2009-03-14)
@changelog_1303_li
@changelog_1308_li
The optimization for IN(...) is now only used if comparing a column with an index.
@changelog_1304_li
@changelog_1309_li
User defined functions can now be deterministic (see CREATE ALIAS documentation).
@changelog_1305_li
@changelog_1310_li
Multiple nested queries in the FROM clause with parameters did not always work.
@changelog_1306_li
@changelog_1311_li
When converting CLOB to BINARY, each character resulted in one byte. Now, the text is parsed as a hex as when converting VARCHAR.
@changelog_1307_li
@changelog_1312_li
New experimental NIO storage mechanism with both FileChannel and memory mapped files. To use it, use the file name prefix nio: or nioMapped: as in jdbc:h2:nio:~/test. So far it looks like NIO storage is faster on Mac OS but slower on some Windows systems. Thanks a lot to Jan Kotek for the patch!
@changelog_1308_li
@changelog_1313_li
The functions BITOR, BITAND, BITXOR, and MOD now accept and return BIGINT instead of INT.
@changelog_1309_li
@changelog_1314_li
Could not use the same linked table multiple times in the same query.
@changelog_1310_li
@changelog_1315_li
Bugs in the server-less multi-connection mode have been fixed.
@changelog_1311_li
@changelog_1316_li
Column names could not be named "UNIQUE" (with the quotes).
@changelog_1312_li
@changelog_1317_li
New system function TRANSACTION_ID() to get the current transaction identifier for a session.
@changelog_1313_h2
@changelog_1318_h2
Version 1.1.108 (2009-02-28)
@changelog_1314_li
@changelog_1319_li
When the shutdown hook closed the database, the last log file was deleted too early. This could cause uncommitted changes to be persisted. In some cases, this could cause data corruption.
@changelog_1315_li
@changelog_1320_li
JdbcConnectionPool: it was possible to set a negative connection pool size.
@changelog_1316_li
@changelog_1321_li
Fulltext search did not support table names with a backslash.
@changelog_1317_li
@changelog_1322_li
The internal IntArray class did not work correctly when initialized with a zero length array.
@changelog_1318_li
@changelog_1323_li
The H2 Console web application (war file) did only support ASCII characters. Now UTF-8 is supported.
@changelog_1319_li
@changelog_1324_li
DATEADD does no longer require that the argument is a timestamp.
@changelog_1320_li
@changelog_1325_li
The database file locking mechanism didn't work correctly on Mac OS.
@changelog_1321_li
@changelog_1326_li
Some built-in functions reported the wrong precision, scale, and display size.
@changelog_1322_li
@changelog_1327_li
MySQL compatibility for CREATE TABLE is improved (UNSIGNED, KEY).
@changelog_1323_li
@changelog_1328_li
Recovery did not work if there were more than 255 lobs stored as files.
@changelog_1324_li
@changelog_1329_li
New experimental mode to support multiple read-write connections without starting a server. To enable this mode, append ;FILE_LOCK=SERIALIZED;OPEN_NEW=TRUE to the database URL. Don't expect high performance when multiple concurrent writers.
@changelog_1325_li
@changelog_1330_li
In a web application, the database classes are not unloaded if a connection is open. This may cause out of memory when re-deploying a web application. The DbStarter is changed to close all connections to the configured database (by executing SHUTDOWN).
@changelog_1326_li
@changelog_1331_li
The WebServlet did not close the database when un-deploying the web application.
@changelog_1327_li
@changelog_1332_li
The exception message of failed INSERT or MERGE statements now includes all values and the row number.
@changelog_1328_li
@changelog_1333_li
If opening a database failed with an out of memory exception, some files were not closed.
@changelog_1329_li
@changelog_1334_li
Optimizer: the expected runtime calculation was incorrect. The fixed calculation should give slightly better query plans when using many joins.
@changelog_1330_li
@changelog_1335_li
Improved exception message when connecting to a just started server fails.
@changelog_1331_li
@changelog_1336_li
Connection.isValid is a bit faster.
@changelog_1332_li
@changelog_1337_li
H2 Console: the autocomplete feature has been improved a bit. It can now better parse conditions.
@changelog_1333_li
@changelog_1338_li
When restarting a web application in Tomcat, an exception was thrown sometimes. In most cases this was a NullPointerException. A workaround in H2 has been implemented. The root cause of the problem is now documented in the FAQ: Tomcat sets all static fields (final or non-final) to null when unloading a web application. A workaround is to put the h2.jar in the lib directory, or set the system property org.apache.catalina.loader.WebappClassLoader.ENABLE_CLEAR_REFERENCES to false.
@changelog_1334_h2
@changelog_1339_h2
Version 1.1.107 (2009-01-24)
@changelog_1335_li
@changelog_1340_li
Some DatabaseMetaData operations did not work for non-admin users for versions 1.1.x.
@changelog_1336_li
@changelog_1341_li
The MySQL compatibility extension fromUnixTime now used the English locale.
@changelog_1337_li
@changelog_1342_li
When using LOG=2 and repeatedly updating the last row rows of a table, the index file grew quickly.
@changelog_1338_li
@changelog_1343_li
In versions 1.1.105 and 1.1.106, encrypted script files of earlier versions could not be processed. This is now again possible. The problem was that such script files were stored in a special format (STORAGE=TEXT) but support for this format was removed in version 1.1.105.
@changelog_1339_li
@changelog_1344_li
Enabling the trace mechanism by creating a specially named file is no longer supported.
@changelog_1340_h2
@changelog_1345_h2
Version 1.1.106 (2009-01-04)
@changelog_1341_li
@changelog_1346_li
Statement.setQueryTimeout did not work correctly for some statements.
@changelog_1342_li
@changelog_1347_li
CREATE DOMAIN: built-in data types can now only be changed if no tables exist.
@changelog_1343_li
@changelog_1348_li
Linked tables: a workaround for Oracle DATE columns has been implemented.
@changelog_1344_li
@changelog_1349_li
DatabaseMetaData.getPrimaryKeys: the column PK_NAME now contains the constraint name instead of the index name (compatibility for PostgreSQL and Derby).
@changelog_1345_li
@changelog_1350_li
Using IN(..) inside a IN(SELECT..) did not always work.
@changelog_1346_li
@changelog_1351_li
Views with IN(..) that used a view itself did not work.
@changelog_1347_li
@changelog_1352_li
Union queries with LIMIT or ORDER BY that are used in a view or subquery did not work.
@changelog_1348_li
@changelog_1353_li
The license change a bit: so far the license was modified to say 'Swiss law'. This is now changed back to the original 'US law'. This was requested by a user, and I don't see a problem.
@changelog_1349_li
@changelog_1354_li
Constraints for local temporary tables now session scoped. So far they were global. Thanks a lot to Eric Faulhaber for finding and fixing this problem!
@changelog_1350_li
@changelog_1355_li
When using the auto-server mode, and if the lock file was modified in the future, the wrong exception was thrown ('Connection is broken' instead of 'Error opening database: lock file modified in the future').
@cheatSheet_1000_h1
...
...
@@ -2707,157 +2722,160 @@ Some problems have been found with right outer join. Internally, it is converted
@faq_1020_li
When using Install4j before 4.1.4 on Linux and enabling <code>pack200</code>, the <code>h2*.jar</code> becomes corrupted by the install process, causing application failure. A workaround is to add an empty file <code>h2*.jar.nopack</code> next to the <code>h2*.jar</code> file. This problem is solved in Install4j 4.1.4.
@faq_1021_h3
@faq_1021_p
For a complete list, see <a href="http://code.google.com/p/h2database/issues/list">Open Issues</a>.
@faq_1022_h3
Is this Database Engine Open Source?
@faq_1022_p
@faq_1023_p
Yes. It is free to use and distribute, and the source code is included. See also under license.
@faq_1023_h3
@faq_1024_h3
My Query is Slow
@faq_1024_p
@faq_1025_p
Slow <code>SELECT</code> (or <code>DELETE, UPDATE, MERGE</code>) statement can have multiple reasons. Follow this checklist:
@faq_1025_li
@faq_1026_li
Run <code>ANALYZE</code> (see documentation for details).
@faq_1026_li
@faq_1027_li
Run the query with <code>EXPLAIN</code> and check if indexes are used (see documentation for details).
@faq_1027_li
@faq_1028_li
If required, create additional indexes and try again using <code>ANALYZE</code> and <code>EXPLAIN</code>.
@faq_1028_li
@faq_1029_li
If it doesn't help please report the problem.
@faq_1029_h3
@faq_1030_h3
How to Create a New Database?
@faq_1030_p
@faq_1031_p
By default, a new database is automatically created if it does not yet exist. See <a href="tutorial.html#creating_new_databases">Creating New Databases</a>.
@faq_1031_h3
@faq_1032_h3
How to Connect to a Database?
@faq_1032_p
@faq_1033_p
The database driver is <code>org.h2.Driver</code>, and the database URL starts with <code>jdbc:h2:</code>. To connect to a database using JDBC, use the following code:
@faq_1033_h3
@faq_1034_h3
Where are the Database Files Stored?
@faq_1034_p
@faq_1035_p
When using database URLs like <code>jdbc:h2:~/test</code>, the database is stored in the user directory. For Windows, this is usually <code>C:\Documents and Settings\<userName></code>. If the base directory is not set (as in <code>jdbc:h2:test</code>), the database files are stored in the directory where the application is started (the current working directory). When using the H2 Console application from the start menu, this is <code><Installation Directory>/bin</code>. The base directory can be set in the database URL. A fixed or relative path can be used. When using the URL <code>jdbc:h2:file:data/sample</code>, the database is stored in the directory <code>data</code> (relative to the current working directory). The directory is created automatically if it does not yet exist. It is also possible to use the fully qualified directory name (and for Windows, drive name). Example: <code>jdbc:h2:file:C:/data/test</code>
@faq_1035_h3
@faq_1036_h3
What is the Size Limit (Maximum Size) of a Database?
@faq_1036_p
@faq_1037_p
See <a href="advanced.html#limits_limitations">Limits and Limitations</a>.
@faq_1037_h3
@faq_1038_h3
Is it Reliable?
@faq_1038_p
@faq_1039_p
That is not easy to say. It is still a quite new product. A lot of tests have been written, and the code coverage of these tests is very high. Randomized stress tests are run regularly. But there are probably still bugs that have not yet been found (as with most software). Some features are known to be dangerous, they are only supported for situations where performance is more important than reliability. Those dangerous features are:
@faq_1039_li
@faq_1040_li
Disabling the transaction log mechanism using <code>SET LOG 0</code>.
@faq_1040_li
@faq_1041_li
Using the transaction isolation level <code>READ_UNCOMMITTED</code> (<code>LOCK_MODE 0</code>) while at the same time using multiple connections.
@faq_1041_li
@faq_1042_li
Disabling database file protection using <code>FILE_LOCK=NO</code> in the database URL.
@faq_1042_li
@faq_1043_li
Disabling referential integrity using <code>SET REFERENTIAL_INTEGRITY FALSE</code>.
@faq_1043_p
@faq_1044_p
In addition to that, running out of memory should be avoided. In older versions, OutOfMemory errors while using the database could corrupt a databases.
@faq_1044_p
@faq_1045_p
Some areas of this database are not fully tested. When using one of those features for production, please ensure your use case is well tested (if possible with automated test cases). Those areas are:
@faq_1045_li
@faq_1046_li
Platforms other than Windows XP, Linux, Mac OS X, or JVMs other than Sun 1.5 or 1.6
@faq_1046_li
@faq_1047_li
The features <code>AUTO_SERVER</code> and <code>AUTO_RECONNECT</code>
@faq_1047_li
@faq_1048_li
The file locking method 'Serialized'
@faq_1048_li
@faq_1049_li
The MVCC (multi version concurrency) mode
@faq_1049_li
@faq_1050_li
Cluster mode, 2-phase commit, savepoints
@faq_1050_li
@faq_1051_li
24/7 operation
@faq_1051_li
@faq_1052_li
Some operations on databases larger than 500 MB may be slower than expected
@faq_1052_li
@faq_1053_li
The optimizer may not always select the best plan
@faq_1053_li
@faq_1054_li
Fulltext search
@faq_1054_li
@faq_1055_li
Operations on LOBs over 2 GB
@faq_1055_p
@faq_1056_p
Areas considered experimental are:
@faq_1056_li
@faq_1057_li
The PostgreSQL server
@faq_1057_li
@faq_1058_li
Multi-threading within the engine using <code>SET MULTI_THREADED=1</code>
@faq_1058_li
@faq_1059_li
Compatibility modes for other databases (only some features are implemented)
@faq_1059_li
@faq_1060_li
The soft reference cache (CACHE_TYPE=SOFT_LRU). It might not improve performance, and out of memory issues have been reported.
@faq_1060_p
@faq_1061_p
Some users have reported that after a power failure, the database can sometimes not be opened because the index file is corrupt. In that case, the index file can be deleted (it is automatically re-created). To avoid this, append <code>;LOG=2</code> to the database URL. See also: <a href="grammar.html#set_log" class="notranslate">SET LOG</a>. This problem will be solved using the new 'page store' mechanism (currently beta).
@faq_1061_h3
@faq_1062_h3
Column Names are Incorrect?
@faq_1062_p
@faq_1063_p
For the query <code>SELECT ID AS X FROM TEST</code> the method <code>ResultSetMetaData.getColumnName()</code> returns <code>ID</code>, I expect it to return <code>X</code>. What's wrong?
@faq_1063_p
@faq_1064_p
This is not a bug. According the the JDBC specification, the method <code>ResultSetMetaData.getColumnName()</code> should return the name of the column and not the alias name. If you need the alias name, use <a href="http://java.sun.com/javase/6/docs/api/java/sql/ResultSetMetaData.html#getColumnLabel(int)"><code>ResultSetMetaData.getColumnLabel()</code></a>. Other database don't work like this (they don't follow the JDBC specification). If you need compatibility with those databases, use the <a href="features.html#compatibility">Compatibility Mode</a>, or set the system property <a href="../javadoc/org/h2/constant/SysProperties.html#h2.aliasColumnName"><code>h2.aliasColumnName</code></a>.
@faq_1064_h3
@faq_1065_h3
Why is Opening my Database Slow?
@faq_1065_p
@faq_1066_p
If it takes a long time to open a database, in most cases it was not closed the last time. This is specially a problem for larger databases. To close a database, close all connections to it before the application ends, or execute the command <code>SHUTDOWN</code>. The database is also closed when the virtual machine exits normally by using a shutdown hook. However killing a Java process or calling <code>Runtime.halt</code> will prevent this. The reason why opening is slow in this situations is that indexes are re-created. If you can not guarantee the database is closed, consider using <a href="grammar.html#set_log" class="notranslate">SET LOG 2</a>.
@faq_1066_p
@faq_1067_p
To find out what the problem is, open the database in embedded mode using the H2 Console. This will print progress information. If you have many lines with 'Creating index' it is an indication that the database was not closed the last time.
@faq_1067_p
@faq_1068_p
Other possible reasons are: the database is very big (many GB), or contains linked tables that are slow to open.
@faq_1068_h3
@faq_1069_h3
Is the GCJ Version Stable? Faster?
@faq_1069_p
@faq_1070_p
The GCJ version is not as stable as the Java version. When running the regression test with the GCJ version, sometimes the application just stops at what seems to be a random point without error message. Currently, the GCJ version is also slower than when using the Sun VM. However, the startup of the GCJ version is faster than when using a VM.
@faq_1070_h3
@faq_1071_h3
How to Translate this Project?
@faq_1071_p
@faq_1072_p
For more information, see <a href="build.html#translating">Build/Translating</a>.
@features_1000_h1
...
...
@@ -4649,7 +4667,7 @@ Function Data Type Mapping
SQL types are mapped to Java classes and vice-versa as in the JDBC API. For details, see <a href="datatypes.html">Data Types</a>. There are two special cases: <code>java.lang.Object</code> is mapped to <code>OTHER</code> (a serialized object). Therefore, <code>java.lang.Object</code> can not be used to match all SQL types (matching all SQL types is not supported). The second special case is <code>Object[]</code>: arrays of any class are mapped to <code>ARRAY</code>.
@features_1596_h3
Functions that require a Connection
Functions That Require a Connection
@features_1597_p
If the first parameter of a Java function is a <code>java.sql.Connection</code>, then the connection to database is provided. This connection does not need to be closed before returning. When calling the method from within the SQL statement, this connection parameter does not need to be (can not be) specified.
...
...
@@ -4658,7 +4676,7 @@ Functions that require a Connection
Functions Throwing an Exception
@features_1599_p
If a function throws an exception, then the current statement is rolled back and the exception is thrown to the application.
If a function throws an exception, then the current statement is rolled back and the exception is thrown to the application. SQLException are directly re-thrown to the calling application; all other exceptions are first converted to a SQLException.
@features_1600_h3
Functions Returning a Result Set
...
...
@@ -5156,7 +5174,7 @@ JaQu
What is JaQu
@jaqu_1012_p
JaQu stands for Java Query and allows to access databases using pure Java. JaQu provides a fluent interface (or internal DSL) for building SQL statements. JaQu replaces SQL, JDBC, and persistence frameworks such as Hibernate. JaQu is something like LINQ for Java (LINQ stands for "language integrated query" and is a Microsoft .NET technology). The following JaQu code:
JaQu stands for Java Query and allows to access databases using pure Java. JaQu provides a fluent interface (or internal DSL) to access a database. JaQu is something like LINQ for Java (LINQ stands for "language integrated query" and is a Microsoft .NET technology). The following JaQu code:
@jaqu_1013_p
stands for the SQL statement:
...
...
@@ -9529,15 +9547,21 @@ UNION: evaluate INTERSECT before UNION (like most other database except Oracle).
@roadmap_1438_li
Delay creating the information schema, and share metadata columns.
@roadmap_1439_h2
@roadmap_1439_li
TCP Server: use a nonce (number used once) to protect unencrypted channels against replay attacks.
@roadmap_1440_h2
Not Planned
@roadmap_1440_li
@roadmap_1441_li
HSQLDB (did) support this: select id i from test where i<0 (other databases don't). Supporting it may break compatibility.
@roadmap_1441_li
@roadmap_1442_li
String.intern (so that Strings can be compared with ==) will not be used because some VMs have problems when used extensively.
@roadmap_1443_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.
#If the database was already closed using SHUTDOWN IMMEDIATELY, closing a second connection could throw a NullPointerException if there was a local temporary table.
#There are known errors on rollback when the page store is disabled and at the same time MVCC is used. See http://code.google.com/p/h2database/issues/detail?id=158
@changelog_1003_li
#Less classes are loaded when using the database in embedded mode.
#The DeleteDbFiles tool deleted all files in the .lob.db directory, even files that didn't belong to the database.
@changelog_1004_li
#Nested UNION/INTERSECT queries with brackets could produce the wrong result if used within a subquery. Example: select count(*) from (select 1 union (select 2 intersect select 2)) x;
#Automatic conversion of old databases to the page store format failed if the database contained LOB files.
@changelog_1005_li
#Comparing an column against a constant expression with a higher precision or length than the column could give wrong results (the expression was truncated before comparing).
#Nested subqueries didn't work for INSERT INTO and IN(..). Example: insert into test ((select 1));
@changelog_1006_li
#Improved PostgreSQL compatibility (support SHOW DEFAULT_TRANSACTION_ISOLATION).
#If the database was already closed using SHUTDOWN IMMEDIATELY, closing a second connection could throw a NullPointerException if there was a local temporary table.
@changelog_1007_li
#Documentation: the javadocs for Csv.write and read used the wrong default charset.
#Less classes are loaded when using the database in embedded mode.
@changelog_1008_li
#MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session could query the table. This is now longer possible.
#The information schema tables are only initialized when needed. This reduces memory usage and speeds up creating in-memory databases. Each in-memory database needs about 8 KB of heap memory.
@changelog_1009_li
#If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
#Nested UNION/INTERSECT queries with brackets could produce the wrong result if used within a subquery. Example: select count(*) from (select 1 union (select 2 intersect select 2)) x;
@changelog_1010_li
#Triggers: INSTEAD OF triggers are now supported. Such triggers can be defined on views.
#Comparing an column against a constant expression with a higher precision or length than the column could give wrong results (the expression was truncated before comparing).
@changelog_1011_li
#MVCC: if the page store is disabled, rollback of multiple rows with the same index key did not work correctly.
#Improved PostgreSQL compatibility (support SHOW DEFAULT_TRANSACTION_ISOLATION).
@changelog_1012_li
#New system property h2.identifiersToUpper. If set to false, identifiers in SQL statements are case sensitive even if they are not quoted.
#Documentation: the javadocs for Csv.write and read used the wrong default charset.
@changelog_1013_li
#Slightly improved performance if the table is already locked.
#MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session could query the table. This is now longer possible.
@changelog_1014_li
#CompressLZF: faster decompression.
#If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
@changelog_1015_li
#PgServer: the wrong size was sent for VARCHAR data. Thanks again to Sergi Vladykin for the patch.
#Triggers: INSTEAD OF triggers are now supported. Such triggers can be defined on views.
@changelog_1016_li
#MVCC: if the page store is disabled, rollback of multiple rows with the same index key did not work correctly.
@changelog_1017_li
#New system property h2.identifiersToUpper. If set to false, identifiers in SQL statements are case sensitive even if they are not quoted.
@changelog_1018_li
#Slightly improved performance if the table is already locked.
@changelog_1019_li
#CompressLZF: faster decompression.
@changelog_1020_li
#PgServer: the wrong size was sent for VARCHAR data. Thanks again to Sergi Vladykin for the patch.
@changelog_1021_li
#Serialized access mode (server-less multi-connection mode): fixed getGeneratedKeys() for sequences.
@changelog_1017_h2
@changelog_1022_h2
#Version 1.2.127 (2010-01-15)
@changelog_1018_li
@changelog_1023_li
#Serialized access mode (server-less multi-connection mode): sequences did not work as expected (there were gaps in generated values when using multiple connections).
@changelog_1019_li
@changelog_1024_li
#Page store: new databases can not be opened with older versions.
@changelog_1020_li
@changelog_1025_li
#Page store: adding data to new database is now faster.
@changelog_1021_li
@changelog_1026_li
#File system: getting the file name from a path is now faster. This should speed up BLOB and CLOB access.
@changelog_1022_li
@changelog_1027_li
#PgServer: incorrect SQL types were returned in result set meta data. Concurrently opening a database could fail (PG catalog initialization was not synchronized). Thanks a lot to Sergi Vladykin for providing the patches!
@changelog_1023_li
@changelog_1028_li
#SHOW COLUMNS did not work correctly if there where multiple indexes on the same columns.
@changelog_1024_li
@changelog_1029_li
#Page store: the wrong write count was written to the database header. This could cause the server-less multi-connection mode to fail.
@changelog_1025_li
@changelog_1030_li
#Result sets larger than 2 GB threw an exception "Negative seek offset". Fixed.
@changelog_1026_li
@changelog_1031_li
#If the system property h2.check was set to false, an ArrayIndexOutOfBoundsException could occur.
@changelog_1027_li
@changelog_1032_li
#Alter table is now supported even if a table has views defined.
@changelog_1028_li
@changelog_1033_li
#Fulltext search: exceptions within the fulltext search package had the wrong SQL state.
@changelog_1029_li
@changelog_1034_li
#The Lucene fulltext search ignored transaction rollback. Fixed using a trigger on rollback.
@changelog_1030_li
@changelog_1035_li
#Trigger can now be called on rollback.
@changelog_1031_li
@changelog_1036_li
#The shell script h2.sh ignored command line line arguments.
@changelog_1032_li
@changelog_1037_li
#When running H2 in the Google AppEngine for Java, a AccessControlException could be thrown when trying to open a read-only database. Fixed.
@changelog_1033_li
@changelog_1038_li
#The user home directory prefix (~) is now only expanded when followed by a slash or backslash, or standing alone.
@changelog_1034_li
@changelog_1039_li
#Native fulltext search: before inserting or deleting data, FT_INIT() had to be called. This is no longer required.
@changelog_1035_li
@changelog_1040_li
#The .trace.db file is now only created if required.
@changelog_1036_li
@changelog_1041_li
#Shell tool: improved PostgreSQL compatibility.
@changelog_1037_li
@changelog_1042_li
#Trying to open a database in read-only mode when a .lock.db file exists will now fail with a nice error message.
@changelog_1038_li
@changelog_1043_li
#H2 Console: data that is too long is now abbreviated as follows: text... (100000 characters). A large binary is abbreviated as follows: abcdef... (100000 bytes).
@changelog_1039_li
@changelog_1044_li
#Faster data conversion from BIGINT or INT to DECIMAL.
@changelog_1040_li
@changelog_1045_li
#Server-less multi-connection mode: try to delete log files if switching between read/write operations.
@changelog_1041_li
@changelog_1046_li
#CompressLZF: Faster decompress and improved javadocs
@changelog_1042_h2
@changelog_1047_h2
#Version 1.2.126 (2009-12-18)
@changelog_1043_li
@changelog_1048_li
#The ChangeFileEncryption tool will now fail with an exception if the database is still in use. The Backup tool will also fail except when running in quiet mode.
@changelog_1044_li
@changelog_1049_li
#CSVREAD: when reading the column names from the CSV file, column names that contain no special characters are considered case insensitive now.
@changelog_1045_li
@changelog_1050_li
#Optimization index conditions of the form 'column=NULL' (which is always false; unlike 'column IS NULL').
@changelog_1046_li
@changelog_1051_li
#Script command and tool: the primary key constraint is now listed before inserting the data. This will result in a smaller database when using the page store.
@changelog_1047_li
@changelog_1052_li
#Statements with IN(SELECT..) conditions could produce the wrong result. Example: index on id, name; query: select * from test where id between 1 and 3 and name in (select 'World').
@changelog_1048_li
@changelog_1053_li
#Statements with IN(..) conditions could produce the wrong result when using views or nested select statements. Example: index on id; index on name; query: select * from (select * from test) where id=1 and name in('a', 'b'). select * from (select * from test) where id=1 and name in('Hello', 'World').
@changelog_1049_li
@changelog_1054_li
#Page store: a rollback of a relatively large transaction could fail with an ArrayIndexOutOfBoundsException or a 'row not found' exception in the PageBtreeIndex in some cases.
@changelog_1050_li
@changelog_1055_li
#JaQu: the decompiler has been improved, and a few test cases already work. It is still incomplete however.
@changelog_1051_li
@changelog_1056_li
#LIKE: any letter is now allowed after the escape character (which is still '\' by default). Previously, an exception was thrown (unlike other databases) if it was not the escape character, '_' or '%'. If the escape character appears at the end of the pattern, the result is it is ignored (like PostgreSQL and MS SQL Server).
@changelog_1052_li
@changelog_1057_li
#The reserve heap memory is no longer used.
@changelog_1053_li
@changelog_1058_li
#Database.checkpoint() could throw a NullPointerException.
@changelog_1054_h2
@changelog_1059_h2
#Version 1.2.125 (2009-12-06)
@changelog_1055_li
@changelog_1060_li
#Lucene fulltext search: the Lucene field names now match the table column names, except if the column names start with _ (in which case another _ is prepended). Unfortunately this change means existing fulltext indexes need to be re-built.
@changelog_1056_li
@changelog_1061_li
#The shell tool now has a very simple statement history.
@changelog_1057_li
@changelog_1062_li
#The zip file system implementation now supports the '~' home directory prefix. Example database URL: jdbc:h2:zip:~/test.zip!/test
@changelog_1058_li
@changelog_1063_li
#Right outer joins on tables that were already 'inner joined' was processed incorrectly.
@changelog_1059_li
@changelog_1064_li
#Temporary files from LOB objects were not deleted early enough when using the server mode.
@changelog_1060_li
@changelog_1065_li
#Trying to alter a temporary table threw a strange exception. It is still not possible to do that, but the exception message is better now.
@changelog_1061_li
@changelog_1066_li
#When the system property h2.maxMemoryRowsDistinct was set, and using SELECT DISTINCT, the temporary table was not correctly dropped. This could cause problems in recovery when the process was killed.
@changelog_1062_li
@changelog_1067_li
#Trigger that are called before a select statement are now supported. This allows to create tables that work like materialized views.
@changelog_1063_li
@changelog_1068_li
#Non-row based triggers were called even if the action didn't match the declared action (INSERT triggers were also called when deleting rows). This has been changed. The MERGE statement calls both INSERT and DELETE triggers.
@changelog_1064_li
@changelog_1069_li
#Statements with IN(..) conditions could produce the wrong result or a data conversion error (since version 1.2.120). Examples: index on id, name, condition: id=1 and name in('Hello', 'x'); index on id, query: select * from (select * from test) where id=1 and name in('Hello', 'World').
@changelog_1065_li
@changelog_1070_li
#The CompressTool was not multithreading safe. Because of this, the following database operations where also not multithreading safe (even when using different databases): the SCRIPT command (only when using compression), the COMPRESS function, and storing CLOB or BLOB data (only when compression is enabled).
@changelog_1066_li
@changelog_1071_li
#The compression algorithm "LZF" is now about 33% faster than before when compressing small block (around 2 KB). It is much faster than Deflate, but the compression ratio is lower. Some of the optimizations are from Sam Van Oort, thanks a lot!
@changelog_1067_li
@changelog_1072_li
#Compressing large blocks of data didn't work when using the "Deflate" compression algorithm. Compressing a lot of data could run out of heap memory.
@changelog_1068_li
@changelog_1073_li
#The test cases don't access the file system directly, this simplifies GAE for Java testing. Thanks to Vince Bonfanti.
@changelog_1069_li
@changelog_1074_li
#More bugs in the server-less multi-connection mode have been fixed.
@changelog_1070_li
@changelog_1075_li
#When running against an old database, the SCRIPT statement could generate a SQL script that contained duplicate indexes (PRIMARY_KEY_E).
@changelog_1071_li
@changelog_1076_li
#JdbcConnectionPool.getConnection() could throw a NullPointerException.
@changelog_1072_li
@changelog_1077_li
#User defined functions: the source code is now available using SELECT SOURCE FROM INFORMATION_SCHEMA.FUNCTION_ALIASES.
@changelog_1073_li
@changelog_1078_li
#User defined functions with source code didn't work after re-opening the database.
@changelog_1074_li
@changelog_1079_li
#The newsfeeds are now Atom 1.0 standard compliant.
@changelog_1075_li
@changelog_1080_li
#The database is now closed after an out of memory exception, because the database could get corrupt otherwise.
@changelog_1076_li
@changelog_1081_li
#Better error message if both AUTO_SERVER and SERIALIZED parameters are set to TRUE.
@changelog_1077_li
@changelog_1082_li
#Drop table did not delete lob files in old file store (not PAGE_STORE).
@changelog_1078_h2
@changelog_1083_h2
#Version 1.2.124 (2009-11-20)
@changelog_1079_li
@changelog_1084_li
#Clustering: there is now a way to detect which cluster instances are running.
@changelog_1080_li
@changelog_1085_li
#ConvertTraceFile: the SQL statement statistics are better formatted (newline are removed).
@changelog_1081_li
@changelog_1086_li
#The file lock thread is now stopped when the database is closed.
@changelog_1082_li
@changelog_1087_li
#Issue 140: the Script tool now supports writing to a stream.
@changelog_1083_li
@changelog_1088_li
#Issue 138: the trace output of Statement.execute(String, int) and executeUpdate was incorrect.
@changelog_1084_li
@changelog_1089_li
#Page store: new databases can not be opened with older versions.
@changelog_1085_li
@changelog_1090_li
#Page store: multi-column indexes didn't work if the cache was very small.
@changelog_1086_li
@changelog_1091_li
#Page store: opening a database could theoretically result in an endless loop.
@changelog_1087_li
@changelog_1092_li
#Page store: adding large indexed columns could get very slow.
@changelog_1088_li
@changelog_1093_li
#Page store: after a duplicate key exception, an ArrayIndexOutOfBoundsException could be thrown (only for very large rows).
@changelog_1089_li
@changelog_1094_li
#Page store: the recover tool sometimes generated a script file that contained duplicate data.
@changelog_1090_li
@changelog_1095_li
#Page store: sometimes opening a read-only database failed.
@changelog_1091_li
@changelog_1096_li
#Page store: opening a database sometimes failed if large rows where updated, or if a table was truncated before.
@changelog_1092_li
@changelog_1097_li
#Page store: when using a very small page size (128 bytes or smaller), writing a large row could result in an endless recursion. This is only a theoretical problem, as the page size is 2 KB.
@changelog_1093_li
@changelog_1098_li
#Page store: getting the min value from a descending index with NULL entries could return the wrong result.
@changelog_1094_li
@changelog_1099_li
#Page store: improved auto-recovery after power failure.
@changelog_1095_li
@changelog_1100_li
#The JDBC client did not detect that it was not talking to an H2 server. This could result in strange exceptions when trying to connect to another kind of server.
@changelog_1096_li
@changelog_1101_li
#User defined functions can be created with source code. Example: CREATE ALIAS HI AS 'String hi() { return "Hello"; }'
@changelog_1097_li
@changelog_1102_li
#Database file lock: the exception "lock file modified in the future" is no longer thrown; instead, opening the file will be delayed by 2 seconds.
@changelog_1098_li
@changelog_1103_li
#Inserting LOBs got slower each time the process was restarted. It could loop endlessly after about 1000 process restarts.
@changelog_1099_li
@changelog_1104_li
#Issue 117: Multi-version concurrency: concurrent MERGE statements now work.
@changelog_1100_li
@changelog_1105_li
#Improved read-only database detection.
@changelog_1101_h2
@changelog_1106_h2
#Version 1.2.123 (2009-11-08)
@changelog_1102_li
@changelog_1107_li
#Page store: new databases can not be opened with older versions.
@changelog_1103_li
@changelog_1108_li
#Page store: updating large rows (rows with more than 2000 bytes of data) could corrupt the database.
@changelog_1104_li
@changelog_1109_li
#Page store: inserting very large rows failed with ArrayIndexOutOfBoundsException.
@changelog_1105_li
@changelog_1110_li
#When using multi-threaded kernel mode, setting disabling locking (LOCK_MODE=0) will now throw an exception. At this time this combination will result in corruption when multiple threads try to update the same table.
@changelog_1106_li
@changelog_1111_li
#The fulltext search methods and fields are now protected instead of private, to make the classes more easily extensible.
@changelog_1107_li
@changelog_1112_li
#The Lucene fulltext search now also returns the score.
@changelog_1108_li
@changelog_1113_li
# New function SCOPE_IDENTITY() to avoid problems when inserting rows in a trigger.
@changelog_1109_li
@changelog_1114_li
#Statement.getGeneratedKeys() returned the wrong value if a trigger changed the identity value after inserting the row.
@changelog_1110_li
@changelog_1115_li
#Improved error messages: identifiers and values are now quoted.
@changelog_1111_li
@changelog_1116_li
#Improved error message when casting a value failed: the column name and type is included in the message.
@changelog_1112_li
@changelog_1117_li
#Improved support for GAE for Java thanks to Vince Bonfanti.
@changelog_1113_h2
@changelog_1118_h2
#Version 1.2.122 (2009-10-28)
@changelog_1114_li
@changelog_1119_li
#The native fulltext search now supports streaming CLOB data.
@changelog_1115_li
@changelog_1120_li
#If the database URL ends with ;PAGE_STORE=TRUE and a database in the old format exists, it is automatically converted to the new page store format if possible. A backup of the database is created first. Automatic conversion is not supported if the database was not closed normally (if it contains uncommitted transactions).
@changelog_1116_li
@changelog_1121_li
#Dropping the current user is now allowed if another admin user exists.
@changelog_1117_li
@changelog_1122_li
#Values of type BINARY or BLOB could not be converted to the data type OTHER.
@changelog_1118_li
@changelog_1123_li
#SHUTDOWN COMPACT now fully compacts the database.
@changelog_1119_li
@changelog_1124_li
#New system properties h2.maxCompactCount and h2.maxCompactTime to allow changing the default behavior (at most 2 seconds compacting when closing the database).
@changelog_1120_li
@changelog_1125_li
#New sorted insert optimization (see Performance / Database Performance Tuning).
@changelog_1121_li
@changelog_1126_li
#Issue 116: The files h2*-sources.jar and h2*-javadoc.jar are now in the Maven repository.
@changelog_1122_li
@changelog_1127_li
#Page store: opening a large database was slow if it was not closed before.
@changelog_1123_li
@changelog_1128_li
#Page store: new write and read counters in the meta data table. Use SELECT * FROM INFORMATION_SCHEMA.SETTINGS WHERE NAME IN( 'info.FILE_WRITE_TOTAL', 'info.FILE_WRITE', 'info.FILE_READ', 'info.CACHE_MAX_SIZE', 'info.CACHE_SIZE')
@changelog_1124_li
@changelog_1129_li
#The SQL syntax is documented using (railroad) diagrams. The diagrams are HTML.
@changelog_1125_li
@changelog_1130_li
#The documentation is no longer available in Japanese because the translation was too much out of sync. Please use the Google translation instead.
@changelog_1126_li
@changelog_1131_li
#Certain queries were not sorted if subselect queries were involved
@changelog_1127_li
@changelog_1132_li
#More bugs in the server-less multi-connection mode have been fixed: 90097 The database is read only, caches must be cleared on reconnect, etc.
@changelog_1128_h2
@changelog_1133_h2
#Version 1.2.121 (2009-10-11)
@changelog_1129_li
@changelog_1134_li
#Better support GaeVFS (Google App Engine Virtual File System) thanks to Thanks to Vince Bonfanti.
@changelog_1130_li
@changelog_1135_li
#CSVREAD didn't close the file. Thanks to Vince Bonfanti for the patch!
@changelog_1131_li
@changelog_1136_li
#If a database in the old format exists, it is now used. The system property is used for new databases, or if databases exist in both formats. In any case, the flag in the URL overrides this logic.
@changelog_1132_li
@changelog_1137_li
#Page store bugs were fixed. Large values in indexed columns could corrupt the index.
@changelog_1133_li
@changelog_1138_li
#The page store did not work when using Retrotranslator (because the Retrotranslator doesn't support Integer.reverse and Long.reverse).
@changelog_1134_li
@changelog_1139_li
#New system property h2.pageStoreTrim to disable shrinking the database when closing (disabled by default, meaning by default the database is trimmed).
@changelog_1135_h2
@changelog_1140_h2
#Version 1.2.120 (2009-10-04)
@changelog_1136_li
@changelog_1141_li
#This is a beta version.
@changelog_1137_li
@changelog_1142_li
#Large updates could throw an ArrayIndexOutOfBoundsException in RowList.writeRow.
@changelog_1138_li
@changelog_1143_li
#In version 1.2, the following system properties are now enabled by default: h2.pageStore, h2.nullConcatIsNull, h2.optimizeInList. The default value for h2.defaultMaxLengthInplaceLob is now 4096 (it was 1024 with version 1.1).
@changelog_1139_li
@changelog_1144_li
#New databases are now stored in the new 'page store' file format. Existing databases are kept in the old file format. To use the old file format, append ;PAGE_STORE=FALSE to the database URL or set the system property h2.pageStore to false.
@changelog_1140_li
@changelog_1145_li
#Issue 125: Renaming primary keys was not persistent. Fixed. Unfortunately, databases created by this version can not be opened with older versions because of this change.
@changelog_1141_li
@changelog_1146_li
#Issue 124: Hibernate schema validation failed for decimal/numeric columns. This problem is fixed in the Hibernate dialect that is included with H2 (src/tools/org/hibernate/dialect/H2Dialect.java.txt), but not in Hibernate yet.
@changelog_1142_li
@changelog_1147_li
#PostgreSQL compatibility: function LASTVAL() as an alias for IDENTITY().
@changelog_1143_li
@changelog_1148_li
#Linked tables now support default values when inserting, updating or merging.
@changelog_1144_li
@changelog_1149_li
#Bugfixes in the page store.
@changelog_1145_li
@changelog_1150_li
#Possibility to set a vendor id in Constants.java, so that unofficial builds are distinguishable from official releases.
@changelog_1146_li
@changelog_1151_li
#Allow writing to linked tables in readonly databases.
@changelog_1147_h2
@changelog_1152_h2
#Version 1.1.119 (2009-09-26)
@changelog_1148_li
@changelog_1153_li
#SQL statements in the exception message are no longer included if they contain '--hide--'.
@changelog_1149_li
@changelog_1154_li
#Temporary local tables did not always work after reconnect if AUTO_SERVER=TRUE
@changelog_1150_li
@changelog_1155_li
#New system property h2.defaultMaxLengthInplaceLob to change the default maximum size of an in-place LOB object.
@changelog_1151_li
@changelog_1156_li
#New system property h2.nullConcatIsNull to change the default null concatenation behavior. The default will be enabled in version 1.2.
@changelog_1152_li
@changelog_1157_li
#The cache algorithm TQ is disabled in this version, because it is unstable, and because the current implementation does not have any measurable advantages over the default.
@changelog_1153_li
@changelog_1158_li
#New committer: Christian Peter. He works for <a href="http://www.docware.com">Docware</a> and helped a lot finding and fixing bugs, and generally improving the database. He is now a committer.
@changelog_1154_li
@changelog_1159_li
#ChangeFileEncryption did not work with Lob subdirectories. Fixed.
@changelog_1155_li
@changelog_1160_li
#Issue 121: JaQu: new simple update and merge methods.
@changelog_1156_li
@changelog_1161_li
#Issue 120: JaQu didn't close result sets.
@changelog_1157_li
@changelog_1162_li
#Issue 119: JaQu creates wrong WHERE conditions on some inputs.
@changelog_1158_li
@changelog_1163_li
#The new page store mechanism is now alpha-level quality. The next release will most likely be "1.2.120 beta" where this mode is enabled by default. To use it right now, append ;PAGE_STORE=TRUE to the database URL. The file format of this mode will probably not change any more.
@changelog_1159_li
@changelog_1164_li
#SELECT COUNT(*) FROM SYSTEM_RANGE(...) returned the wrong result. Fixed.
@changelog_1160_li
@changelog_1165_li
#The Recover tool now also processes the log files, however applying those changes is still a manual process.
@changelog_1161_li
@changelog_1166_li
#New sample application that shows how to pass data to a trigger.
@changelog_1162_li
@changelog_1167_li
#More bugs in the server-less multi-connection mode have been fixed: On Windows, two processes could write to the same database at the same time.
@changelog_1163_li
@changelog_1168_li
#When loading triggers or other client classes (static functions, database event listener, user aggregate functions, other JDBC drivers), the database now uses the context class loader if the class could not be found using Class.forName().
@changelog_1164_li
@changelog_1169_li
#Updating many rows with the same CLOB or BLOB values could result in FileNotFoundException.
@changelog_1165_li
@changelog_1170_li
#Statement.getConnection() threw an exception if the connection was already closed.
@changelog_1166_li
@changelog_1171_li
#The native fulltext index kept a reference to a database after the database was closed.
@changelog_1167_li
@changelog_1172_li
#Non-unique in-memory hash indexes are now supported. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1168_li
@changelog_1173_li
#The optimizer does a better job for joins if indexes are missing.
@changelog_1169_h2
@changelog_1174_h2
#Version 1.1.118 (2009-09-04)
@changelog_1170_li
@changelog_1175_li
#SHOW COLUMNS only listed indexed columns.
@changelog_1171_li
@changelog_1176_li
#When calling SHUTDOWN IMMEDIATELY in the server mode, the .trace.db file was not closed.
@changelog_1172_li
@changelog_1177_li
#DatabaseMetaData.getPrimaryKeys: the wrong constraint name was reported if there was another constraint on the same table and columns.
@changelog_1173_li
@changelog_1178_li
#AUTO_INCREMENT now works in the same way in ALTER TABLE ALTER COLUMN as in CREATE TABLE (it does not create a primary key).
@changelog_1174_li
@changelog_1179_li
#Native fulltext search: before searching, FT_INIT() had to be called. This is no longer required.
@changelog_1175_li
@changelog_1180_li
#Better support GaeVFS (Google App Engine Virtual File System).
@changelog_1176_li
@changelog_1181_li
#JaQu: the plan is to support natural (pure Java / Scala) conditions such as (id == 1 && name.equals("Test")). A proof of concept decompiler is now included (it doesn't work yet).
@changelog_1177_li
@changelog_1182_li
#Various bugfixes and improvements in the page store mechanism (still experimental).
@changelog_1178_li
@changelog_1183_li
#PreparedStatement.setObject now converts a java.lang.Character to a string.
@changelog_1179_li
@changelog_1184_li
#H2 Console: PierPaolo Ucchino has completed the Italian translation. Thanks a lot!
@changelog_1180_li
@changelog_1185_li
#Various tools now use Java 5 var-args, such as main the methods and SimpleResultSet.addRow.
@changelog_1181_li
@changelog_1186_li
#H2 Console: indexes of tables of non-default schemas are now also listed.
@changelog_1182_li
@changelog_1187_li
#Issue 111: Multi-version concurrency / duplicate primary key after rollback.
@changelog_1183_li
@changelog_1188_li
#Issue 110: Multi-version concurrency / wrong exception is thrown.
@changelog_1184_li
@changelog_1189_li
#Parser: sequenceName.NEXTVAL and CURRVAL did not respect the schema search path.
@changelog_1185_li
@changelog_1190_li
#Issue 101: The following sequence could throw the exception "Row not found when trying to delete": start a transaction, insert many rows, delete many rows, rollback. The number of rows depends on the cache size.
@changelog_1186_li
@changelog_1191_li
#The stack trace of very common exceptions is no longer written to the .trace.db file by default.
@changelog_1187_li
@changelog_1192_li
#An optimization for OR is implemented, but disabled by default. Expressions of the type X=1 OR X=2 are converted to X IN(1, 2). To enable, set the system property h2.optimizeInList to true before loading the H2 JDBC driver.
@changelog_1188_li
@changelog_1193_li
#An optimization for IN(..) and IN(SELECT...) is implemented, but disabled by default. To enable, set the system property h2.optimizeInList to true before loading the H2 JDBC driver. If enabled, this overrides h2.optimizeIn and h2.optimizeInJoin. Unlike now, this optimization will also speed up updates and deletes.
@changelog_1189_h2
@changelog_1194_h2
#Version 1.1.117 (2009-08-09)
@changelog_1190_li
@changelog_1195_li
#New committer: Sam Van Oort has been contributing to H2 since quite some time in many ways (on the mailing list, documentation, and in the form of patches). He is now a committer.
@changelog_1191_li
@changelog_1196_li
#JaQu: the order of the fields in the database no longer needs to match the order in the database.
@changelog_1192_li
@changelog_1197_li
#Issue 103: MVCC: the setting MAX_MEMORY_UNDO can currently not be supported when using multi-version concurrency, that means the complete undo log must fit in memory.
@changelog_1193_li
@changelog_1198_li
#LIKE: the escape mechanism can now be disable using ESCAPE ''. The default escape character can be changed using the system property h2.defaultEscape. The default is still '\' (as in MySQL and PostgreSQL).
@changelog_1194_li
@changelog_1199_li
#Views using functions were not re-evaluated when necessary.
@changelog_1195_li
@changelog_1200_li
#Improved MySQL compatibility for SHOW COLUMNS.
@changelog_1196_li
@changelog_1201_li
#Improved PostgreSQL compatibility for timestamp literals with timezone.
@changelog_1197_li
@changelog_1202_li
#Sergi Vladykin translated the error messages to Russian. Thanks a lot!
@changelog_1198_li
@changelog_1203_li
#Support for Java 6 DatabaseMetaData.getTables, getColumns, getProcedures, and getProcedureColumns.
@changelog_1199_li
@changelog_1204_li
#Issue 101: Rollback of a large transaction (more than 100000 rows) could fail.
@changelog_1200_li
@changelog_1205_li
#Various bugfixes and improvements in the page store mechanism (still experimental).
@changelog_1201_li
@changelog_1206_li
#The functions LENGTH, OCTET_LENGTH, and BIT_LENGTH now return BIGINT.
@changelog_1202_li
@changelog_1207_li
#Data types CLOB and BLOB: the maximum precision was Integer.MAX_VALUE, it is now Long.MAX_VALUE.
@changelog_1203_li
@changelog_1208_li
#Multi-threaded kernel: creating and dropping temporary database objects and the potentially free pages list was not correctly synchronized. Thanks a lot to Eric Faulhaber for the test case and patch!
@changelog_1204_li
@changelog_1209_li
#Parsing SQL script files is now faster.
@changelog_1205_li
@changelog_1210_li
#CSV reading is now faster.
@changelog_1206_li
@changelog_1211_li
#SimpleResultSet.newInstance(SimpleRowSource rs) did not work.
@changelog_1207_h2
@changelog_1212_h2
#Version 1.1.116 (2009-07-18)
@changelog_1208_li
@changelog_1213_li
#Server-less multi-connection mode: more bugs are fixed.
@changelog_1209_li
@changelog_1214_li
#The built-in help (INFORMATION_SCHEMA.HELP) is smaller, shrinking the jar file size a bit.
@changelog_1210_li
@changelog_1215_li
#H2 Console: column of tables of non-default schemas are now also listed, except for schemas starting with 'INFO'.
@changelog_1211_li
@changelog_1216_li
#ALTER TABLE: removing an auto-increment or identity column didn't remove the sequence.
@changelog_1212_li
@changelog_1217_li
#Creating indexes is now a bit faster.
@changelog_1213_li
@changelog_1218_li
#PG Server: new system property h2.pgClientEncoding to explicitly set the encoding for clients that don't send the encoding (the default encoding is UTF-8). Thanks a lot to Sergi Vladykin for the patch!
@changelog_1214_li
@changelog_1219_li
#PG Server: improved compatibility by using the type ids of the PostgreSQL driver. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1215_li
@changelog_1220_li
#H2 Console: Oracle system tables are no longer listed, improving performance.
@changelog_1216_li
@changelog_1221_li
#Result sets are now read-only except if the statement or prepared statement was created with the concurrency ResultSet.CONCUR_UPDATABLE. This change is required because the old behavior (all result set are updatable) violated the JDBC spec. For backward compatibility, use the system property h2.defaultResultSetConcurrency.
@changelog_1217_li
@changelog_1222_li
#New system property h2.defaultResultSetConcurrency to change the default result set concurrency.
@changelog_1218_li
@changelog_1223_li
#JDBC: using an invalid result set type or concurrency now throws an exception.
@changelog_1219_li
@changelog_1224_li
#If a pooled connection was not closed but garbage collected, a NullPointerException could occur.
@changelog_1220_li
@changelog_1225_li
#Fulltext search: a NullPointerException was thrown when updating a value that was NULL previously.
@changelog_1221_li
@changelog_1226_li
#The Recover tool did not work with .data.db files of the wrong size.
@changelog_1222_li
@changelog_1227_li
#Triggers: if there was an exception when initializing a trigger, this exception could be hidden, and in some cases (specially when using the Lucene fulltext index mechanism) a NullPointerException was thrown later on. Now the exception that occurred on init is thrown when changing data.
@changelog_1223_li
@changelog_1228_li
#The soft-references cache (CACHE_TYPE=SOFT_LRU) could throw a NullPointerException.
@changelog_1224_li
@changelog_1229_li
#To enable the new page store mechanism, append ;PAGE_STORE=TRUE to the database URL. or set the system property h2.pageStore to true. This mechanism is still experimental, and the file format will change, but it is quite stable now.
@changelog_1225_h2
@changelog_1230_h2
#Version 1.1.115 (2009-06-21)
@changelog_1226_li
@changelog_1231_li
#The new storage mechanism is now alpha quality. To try it out, set the system property "h2.pageStore" to "true" (java -Dh2.pageStore=true). There are still bugs to be found and fixed, for example inserting many rows references a lot of main memory. Performance is currently about the same as with the regular storage mechanism, but the database file size is smaller. The file format is not stable yet.
@changelog_1227_li
@changelog_1232_li
#ALTER TABLE could throw an exception "object already exists" in some cases.
@changelog_1228_li
@changelog_1233_li
#Views: in some situations, an ArrayIndexOutOfBoundsException was thrown when using the same view concurrently.
@changelog_1229_li
@changelog_1234_li
#java.util.UUID is now supported in PreparedStatement.setObject and user defined Java functions. ResultSet.getObject() returns a java.util.UUID when using the UUID data type.
@changelog_1230_li
@changelog_1235_li
#H2 Console: the language was reset to the browser language when disconnecting.
@changelog_1231_li
@changelog_1236_li
#H2 Console: improved Polish translation.
@changelog_1232_li
@changelog_1237_li
#Server-less multi-connection mode: more bugs are fixed.
@changelog_1233_li
@changelog_1238_li
#The download page now included the SHA1 checksums.
@changelog_1234_li
@changelog_1239_li
#Shell tool: the file encoding workaround is now documented if you run java org.h2.tools.Shell -?.
@changelog_1235_li
@changelog_1240_li
#The RunScript tool and SQL statement did not work with the compression method LZF.
@changelog_1236_li
@changelog_1241_li
#Fulltext search: searching for NULL or an empty string threw an exception.
@changelog_1237_li
@changelog_1242_li
#Lucene fulltext search: FTL_DROP_ALL did not drop the triggers.
@changelog_1238_li
@changelog_1243_li
#Backup: if the database contained CLOB or BLOB data, the backup included a file entry for the LOB directory. This caused the restore to fail.
@changelog_1239_li
@changelog_1244_li
#Data types: LONG is now an alias for BIGINT.
@changelog_1240_h2
@changelog_1245_h2
#Version 1.1.114 (2009-06-01)
@changelog_1241_li
@changelog_1246_li
#ResultSetMetaData.getColumnClassName returned the wrong class for CLOB and BLOB columns.
@changelog_1242_li
@changelog_1247_li
#Fulltext search: data is no longer deleted and re-inserted if the indexed columns didn't change.
@changelog_1243_li
@changelog_1248_li
#In some situations, an ArrayIndexOutOfBoundsException was thrown when adding rows. This was caused by a bug in the b-tree code.
@changelog_1244_li
@changelog_1249_li
#Microsoft Windows Vista: when using the the installer, Vista wrote "This program may not have installed correctly." This message should no longer appear (in the h2.nsi file, the line 'RequestExecutionLevel highest' was added).
@changelog_1245_li
@changelog_1250_li
#The Recover tool did not always work when the database contains referential integrity constraints.
@changelog_1246_li
@changelog_1251_li
#Java 1.5 is now required to run H2. If required, Retrotranslator can be used to create a Java 1.4 version (http://retrotranslator.sourceforge.net/).
@changelog_1247_h2
@changelog_1252_h2
#Version 1.1.113 (2009-05-21)
@changelog_1248_li
@changelog_1253_li
#Shell tool: the built-in commands EXIT, HELP, ?, LIST, and so on didn't work with a semicolon at the end.
@changelog_1249_li
@changelog_1254_li
#JDK 1.5 is now required to build the jar file. However it is still possible to create a jar file for Java 1.4. For details, see buildRelease.sh and buildRelease.bat. As an alternative, compile using JDK 1.5 or 1.6 and use Retrotranslator to create a Java 1.4 version (http://retrotranslator.sourceforge.net/).
@changelog_1250_li
@changelog_1255_li
#When deleting or updating many rows in a table, the space in the index file was not re-used in the default mode (persistent database, b-tree index, LOG=1). This caused the index file to grow over time. Workarounds were to delete and re-created the index file, alter the table (add a remove a column), or append ;LOG=2 to the database URL. To disable the change, set the system property h2.reuseSpaceBtreeIndex to false.
@changelog_1251_li
@changelog_1256_li
#Identifiers with a digit and then a dollar sign didn't work. Example: A1$B.
@changelog_1252_li
@changelog_1257_li
#MS SQL Server compatibility: support for linked tables with NVARCHAR, NCHAR, NCLOB, and LONGNVARCHAR.
@changelog_1253_li
@changelog_1258_li
#Android: workaround for a problem when using read-only databases in zip files (skip seems to be implemented incorrectly on the Android system).
@changelog_1254_li
@changelog_1259_li
#Calling execute() or prepareStatement() with null as the SQL statement now throws an exception.
@changelog_1255_li
@changelog_1260_li
#Benchmark: the number of executed statements was incorrect. The H2 database was loaded at the beginning of the test to collect results, now it is loaded at the very end. Thanks to Fred Toussi from HSQLDB for reporting those problems. However the changed do not affect the relative performance.
@changelog_1256_li
@changelog_1261_li
#H2 Console: command line settings are no longer stored in the properties file. They are now only used for the current process, except if they are explicitly saved.
@changelog_1257_li
@changelog_1262_li
#Cache: support for a second level soft-references cache. To enable it, append ;CACHE_TYPE=SOFT_LRU (or SOFT_TQ) to the database URL, or set the system property h2.cacheTypeDefault to "SOFT_LRU" / "SOFT_TQ". Enabling the second level cache reduces performance for small databases, but speeds up large databases. It makes sense to use it if the available memory size is unknown. Thanks a lot to Jan Kotek!
@changelog_1258_h2
@changelog_1263_h2
#Version 1.1.112 (2009-05-01)
@changelog_1259_li
@changelog_1264_li
#JdbcPreparedStatement.toString() could throw a NullPointerException.
#Connection pool: the default login timeout is now 5 minutes.
@changelog_1262_li
@changelog_1267_li
#After truncating tables, opening large databases could become slow because indexes were always re-built unnecessarily when opening.
@changelog_1263_li
@changelog_1268_li
#More bugs in the server-less multi-connection mode have been fixed: Sometimes parameters of prepared statements were lost when a reconnecting. Concurrent read operations were slow. To improve performance, executeQuery(..) must be used for queries (execute(..) switches to the write mode, which is slow).
@changelog_1264_li
@changelog_1269_li
#GROUP BY queries with a self-join (join to the same table) that were grouped by columns with indexes returned the wrong result in some cases.
@changelog_1265_li
@changelog_1270_li
#Improved error message when the .lock.db file modification time is in the future.
@changelog_1266_li
@changelog_1271_li
#The MERGE statement now returns 0 as the generated key if the row was updated.
@changelog_1267_li
@changelog_1272_li
#Running code coverage is now automated.
@changelog_1268_li
@changelog_1273_li
#A file system implementation can now be registered using FileSystem.register.
@changelog_1269_li
@changelog_1274_li
#The database file system is no longer included in the jar file, it moved to the test section.
@changelog_1270_h2
@changelog_1275_h2
#Version 1.1.111 (2009-04-10)
@changelog_1271_li
@changelog_1276_li
#In-memory databases can now run inside the Google App Engine.
@changelog_1272_li
@changelog_1277_li
#Queries that are ordered by an indexed column returned no rows in certain cases (if all rows were deleted from the table previously, and there is a low number of rows in the table, and when not using other conditions, and when using the default b tree index).
@changelog_1273_li
@changelog_1278_li
#The wrong exception was thrown when using unquoted text for the SQL statements COMMENT, ALTER USER, and SET PASSWORD.
@changelog_1274_li
@changelog_1279_li
#The built-in connection pool did not roll back transactions and enable autocommit enabled after closing a connection.
@changelog_1275_li
@changelog_1280_li
#Sometimes a StackOverflow occurred when checking for deadlock. See also http://code.google.com/p/h2database/issues/detail?id=61
@changelog_1276_li
@changelog_1281_li
#The Shell tool no longer truncates results with only one column, and displays a message if data was truncated.
@changelog_1277_h2
@changelog_1282_h2
#Version 1.1.110 (2009-04-03)
@changelog_1278_li
@changelog_1283_li
#Support for not persistent in-memory tables in regular (persistent) databases using CREATE MEMORY TABLE(..) NOT PERSISTENT. Thanks a lot to Sergi Vladykin for the patch!
@changelog_1279_li
@changelog_1284_li
#The H2 Console trimmed the password (removed leading and trailing spaces). This is no longer the case, to support encrypted H2 database with an empty user password.
@changelog_1280_li
@changelog_1285_li
#The data type of a SUBSTRING method was wrong.
@changelog_1281_li
@changelog_1286_li
#ResultSet.findColumn and get methods with column label parameters now also check for matching column names (like most databases except MySQL).
@changelog_1282_li
@changelog_1287_li
#H2 Console: the browser system property now supports a list of arguments. Example: java -Dh2.browser="open,-a,Safari,%url" ...
@changelog_1283_li
@changelog_1288_li
#Improved Javadoc navigation (similar to Scaladoc).
@changelog_1284_li
@changelog_1289_li
#H2 Console: auto-complete of identifiers did not work correctly for H2 databases in MySQL mode.
@changelog_1285_li
@changelog_1290_li
#DISTINCT and GROUP BY on a CLOB column was broken.
@changelog_1286_li
@changelog_1291_li
#The FTP server moved to the tools section and is no longer included in the h2*.jar file.
@changelog_1287_li
@changelog_1292_li
#Improved error message for unsupported features: now the message says what exactly is not supported.
@changelog_1288_li
@changelog_1293_li
#Improved OSGi support.
@changelog_1289_li
@changelog_1294_li
#Some internal caches did not use the LRU mechanism. Fixed (LOB file list, optimizer cost cache, trace system, view indexes, collection keys, compressed in-memory file system).
@changelog_1290_li
@changelog_1295_li
#The API of the tools changed a bit (each tool now returns an exit code).
@changelog_1291_li
@changelog_1296_li
#Command line help of the tools now match the javadocs. The build converts the javadocs to a resource that is read by the tool at runtime. This should not have an effect on using the database, but it reduces duplicate and out-of-sync documentation.
@changelog_1292_li
@changelog_1297_li
#CREATE TABLE: improved compatibility (support for UNIQUE NOT NULL).
@changelog_1293_li
@changelog_1298_li
#DatabaseMetaData.getSQLKeywords now returns the correct list.
@changelog_1294_li
@changelog_1299_li
#Deterministic user defined functions did not work when the parameter was a column. Fixed.
@changelog_1295_li
@changelog_1300_li
#JdbcConnectionPool.setLoginTimeout with 0 now uses the default timeout.
@changelog_1296_li
@changelog_1301_li
#Creating a JdbcConnectionPool has been simplified a bit.
@changelog_1297_li
@changelog_1302_li
#The built-in connection pool did not re-use connections. Getting a connection using the built-in JdbcConnectionPool is now about 70 times faster than opening connections using DriverManager.getConnection.
@changelog_1298_li
@changelog_1303_li
#More bugs in the server-less multi-connection mode have been fixed: If a process terminated while writing, other open connections were blocked. If two processes were writing to the database, sometimes the database was corrupt after closing.
@changelog_1299_li
@changelog_1304_li
#Linked tables to SQLite database can now be created.
@changelog_1300_li
@changelog_1305_li
#Nested IN(IN(...)) didn't work.
@changelog_1301_li
@changelog_1306_li
#NIO storage: the nio: prefix was using memory mapped files instead of FileChannel.
@changelog_1302_h2
@changelog_1307_h2
#Version 1.1.109 (2009-03-14)
@changelog_1303_li
@changelog_1308_li
#The optimization for IN(...) is now only used if comparing a column with an index.
@changelog_1304_li
@changelog_1309_li
#User defined functions can now be deterministic (see CREATE ALIAS documentation).
@changelog_1305_li
@changelog_1310_li
#Multiple nested queries in the FROM clause with parameters did not always work.
@changelog_1306_li
@changelog_1311_li
#When converting CLOB to BINARY, each character resulted in one byte. Now, the text is parsed as a hex as when converting VARCHAR.
@changelog_1307_li
@changelog_1312_li
#New experimental NIO storage mechanism with both FileChannel and memory mapped files. To use it, use the file name prefix nio: or nioMapped: as in jdbc:h2:nio:~/test. So far it looks like NIO storage is faster on Mac OS but slower on some Windows systems. Thanks a lot to Jan Kotek for the patch!
@changelog_1308_li
@changelog_1313_li
#The functions BITOR, BITAND, BITXOR, and MOD now accept and return BIGINT instead of INT.
@changelog_1309_li
@changelog_1314_li
#Could not use the same linked table multiple times in the same query.
@changelog_1310_li
@changelog_1315_li
#Bugs in the server-less multi-connection mode have been fixed.
@changelog_1311_li
@changelog_1316_li
#Column names could not be named "UNIQUE" (with the quotes).
@changelog_1312_li
@changelog_1317_li
#New system function TRANSACTION_ID() to get the current transaction identifier for a session.
@changelog_1313_h2
@changelog_1318_h2
#Version 1.1.108 (2009-02-28)
@changelog_1314_li
@changelog_1319_li
#When the shutdown hook closed the database, the last log file was deleted too early. This could cause uncommitted changes to be persisted. In some cases, this could cause data corruption.
@changelog_1315_li
@changelog_1320_li
#JdbcConnectionPool: it was possible to set a negative connection pool size.
@changelog_1316_li
@changelog_1321_li
#Fulltext search did not support table names with a backslash.
@changelog_1317_li
@changelog_1322_li
#The internal IntArray class did not work correctly when initialized with a zero length array.
@changelog_1318_li
@changelog_1323_li
#The H2 Console web application (war file) did only support ASCII characters. Now UTF-8 is supported.
@changelog_1319_li
@changelog_1324_li
#DATEADD does no longer require that the argument is a timestamp.
@changelog_1320_li
@changelog_1325_li
#The database file locking mechanism didn't work correctly on Mac OS.
@changelog_1321_li
@changelog_1326_li
#Some built-in functions reported the wrong precision, scale, and display size.
@changelog_1322_li
@changelog_1327_li
#MySQL compatibility for CREATE TABLE is improved (UNSIGNED, KEY).
@changelog_1323_li
@changelog_1328_li
#Recovery did not work if there were more than 255 lobs stored as files.
@changelog_1324_li
@changelog_1329_li
#New experimental mode to support multiple read-write connections without starting a server. To enable this mode, append ;FILE_LOCK=SERIALIZED;OPEN_NEW=TRUE to the database URL. Don't expect high performance when multiple concurrent writers.
@changelog_1325_li
@changelog_1330_li
#In a web application, the database classes are not unloaded if a connection is open. This may cause out of memory when re-deploying a web application. The DbStarter is changed to close all connections to the configured database (by executing SHUTDOWN).
@changelog_1326_li
@changelog_1331_li
#The WebServlet did not close the database when un-deploying the web application.
@changelog_1327_li
@changelog_1332_li
#The exception message of failed INSERT or MERGE statements now includes all values and the row number.
@changelog_1328_li
@changelog_1333_li
#If opening a database failed with an out of memory exception, some files were not closed.
@changelog_1329_li
@changelog_1334_li
#Optimizer: the expected runtime calculation was incorrect. The fixed calculation should give slightly better query plans when using many joins.
@changelog_1330_li
@changelog_1335_li
#Improved exception message when connecting to a just started server fails.
@changelog_1331_li
@changelog_1336_li
#Connection.isValid is a bit faster.
@changelog_1332_li
@changelog_1337_li
#H2 Console: the autocomplete feature has been improved a bit. It can now better parse conditions.
@changelog_1333_li
@changelog_1338_li
#When restarting a web application in Tomcat, an exception was thrown sometimes. In most cases this was a NullPointerException. A workaround in H2 has been implemented. The root cause of the problem is now documented in the FAQ: Tomcat sets all static fields (final or non-final) to null when unloading a web application. A workaround is to put the h2.jar in the lib directory, or set the system property org.apache.catalina.loader.WebappClassLoader.ENABLE_CLEAR_REFERENCES to false.
@changelog_1334_h2
@changelog_1339_h2
#Version 1.1.107 (2009-01-24)
@changelog_1335_li
@changelog_1340_li
#Some DatabaseMetaData operations did not work for non-admin users for versions 1.1.x.
@changelog_1336_li
@changelog_1341_li
#The MySQL compatibility extension fromUnixTime now used the English locale.
@changelog_1337_li
@changelog_1342_li
#When using LOG=2 and repeatedly updating the last row rows of a table, the index file grew quickly.
@changelog_1338_li
@changelog_1343_li
#In versions 1.1.105 and 1.1.106, encrypted script files of earlier versions could not be processed. This is now again possible. The problem was that such script files were stored in a special format (STORAGE=TEXT) but support for this format was removed in version 1.1.105.
@changelog_1339_li
@changelog_1344_li
#Enabling the trace mechanism by creating a specially named file is no longer supported.
@changelog_1340_h2
@changelog_1345_h2
#Version 1.1.106 (2009-01-04)
@changelog_1341_li
@changelog_1346_li
#Statement.setQueryTimeout did not work correctly for some statements.
@changelog_1342_li
@changelog_1347_li
#CREATE DOMAIN: built-in data types can now only be changed if no tables exist.
@changelog_1343_li
@changelog_1348_li
#Linked tables: a workaround for Oracle DATE columns has been implemented.
@changelog_1344_li
@changelog_1349_li
#DatabaseMetaData.getPrimaryKeys: the column PK_NAME now contains the constraint name instead of the index name (compatibility for PostgreSQL and Derby).
@changelog_1345_li
@changelog_1350_li
#Using IN(..) inside a IN(SELECT..) did not always work.
@changelog_1346_li
@changelog_1351_li
#Views with IN(..) that used a view itself did not work.
@changelog_1347_li
@changelog_1352_li
#Union queries with LIMIT or ORDER BY that are used in a view or subquery did not work.
@changelog_1348_li
@changelog_1353_li
#The license change a bit: so far the license was modified to say 'Swiss law'. This is now changed back to the original 'US law'. This was requested by a user, and I don't see a problem.
@changelog_1349_li
@changelog_1354_li
#Constraints for local temporary tables now session scoped. So far they were global. Thanks a lot to Eric Faulhaber for finding and fixing this problem!
@changelog_1350_li
@changelog_1355_li
#When using the auto-server mode, and if the lock file was modified in the future, the wrong exception was thrown ('Connection is broken' instead of 'Error opening database: lock file modified in the future').
@cheatSheet_1000_h1
...
...
@@ -2707,157 +2722,160 @@ F A Q
@faq_1020_li
#When using Install4j before 4.1.4 on Linux and enabling <code>pack200</code>, the <code>h2*.jar</code> becomes corrupted by the install process, causing application failure. A workaround is to add an empty file <code>h2*.jar.nopack</code> next to the <code>h2*.jar</code> file. This problem is solved in Install4j 4.1.4.
@faq_1021_h3
@faq_1021_p
# For a complete list, see <a href="http://code.google.com/p/h2database/issues/list">Open Issues</a>.
@faq_1022_h3
このデータベースエンジンはオープンソースですか？
@faq_1022_p
@faq_1023_p
# Yes. It is free to use and distribute, and the source code is included. See also under license.
@faq_1023_h3
@faq_1024_h3
#My Query is Slow
@faq_1024_p
@faq_1025_p
# Slow <code>SELECT</code> (or <code>DELETE, UPDATE, MERGE</code>) statement can have multiple reasons. Follow this checklist:
@faq_1025_li
@faq_1026_li
#Run <code>ANALYZE</code> (see documentation for details).
@faq_1026_li
@faq_1027_li
#Run the query with <code>EXPLAIN</code> and check if indexes are used (see documentation for details).
@faq_1027_li
@faq_1028_li
#If required, create additional indexes and try again using <code>ANALYZE</code> and <code>EXPLAIN</code>.
@faq_1028_li
@faq_1029_li
#If it doesn't help please report the problem.
@faq_1029_h3
@faq_1030_h3
新規データベースの構築方法は？
@faq_1030_p
@faq_1031_p
# By default, a new database is automatically created if it does not yet exist. See <a href="tutorial.html#creating_new_databases">Creating New Databases</a>.
@faq_1031_h3
@faq_1032_h3
データベースへの接続方法は？
@faq_1032_p
@faq_1033_p
# The database driver is <code>org.h2.Driver</code>, and the database URL starts with <code>jdbc:h2:</code>. To connect to a database using JDBC, use the following code:
@faq_1033_h3
@faq_1034_h3
データベースのファイルはどこに保存されますか？
@faq_1034_p
@faq_1035_p
# When using database URLs like <code>jdbc:h2:~/test</code>, the database is stored in the user directory. For Windows, this is usually <code>C:\Documents and Settings\<userName></code>. If the base directory is not set (as in <code>jdbc:h2:test</code>), the database files are stored in the directory where the application is started (the current working directory). When using the H2 Console application from the start menu, this is <code><Installation Directory>/bin</code>. The base directory can be set in the database URL. A fixed or relative path can be used. When using the URL <code>jdbc:h2:file:data/sample</code>, the database is stored in the directory <code>data</code> (relative to the current working directory). The directory is created automatically if it does not yet exist. It is also possible to use the fully qualified directory name (and for Windows, drive name). Example: <code>jdbc:h2:file:C:/data/test</code>
@faq_1035_h3
@faq_1036_h3
#What is the Size Limit (Maximum Size) of a Database?
@faq_1036_p
@faq_1037_p
# See <a href="advanced.html#limits_limitations">Limits and Limitations</a>.
@faq_1037_h3
@faq_1038_h3
これは信頼できるデータベースですか？
@faq_1038_p
@faq_1039_p
# That is not easy to say. It is still a quite new product. A lot of tests have been written, and the code coverage of these tests is very high. Randomized stress tests are run regularly. But there are probably still bugs that have not yet been found (as with most software). Some features are known to be dangerous, they are only supported for situations where performance is more important than reliability. Those dangerous features are:
@faq_1039_li
@faq_1040_li
#Disabling the transaction log mechanism using <code>SET LOG 0</code>.
@faq_1040_li
@faq_1041_li
#Using the transaction isolation level <code>READ_UNCOMMITTED</code> (<code>LOCK_MODE 0</code>) while at the same time using multiple connections.
@faq_1041_li
@faq_1042_li
#Disabling database file protection using <code>FILE_LOCK=NO</code> in the database URL.
@faq_1042_li
@faq_1043_li
#Disabling referential integrity using <code>SET REFERENTIAL_INTEGRITY FALSE</code>.
@faq_1043_p
@faq_1044_p
# In addition to that, running out of memory should be avoided. In older versions, OutOfMemory errors while using the database could corrupt a databases.
@faq_1044_p
@faq_1045_p
# Some areas of this database are not fully tested. When using one of those features for production, please ensure your use case is well tested (if possible with automated test cases). Those areas are:
@faq_1045_li
@faq_1046_li
#Platforms other than Windows XP, Linux, Mac OS X, or JVMs other than Sun 1.5 or 1.6
@faq_1046_li
@faq_1047_li
#The features <code>AUTO_SERVER</code> and <code>AUTO_RECONNECT</code>
@faq_1047_li
@faq_1048_li
#The file locking method 'Serialized'
@faq_1048_li
@faq_1049_li
#The MVCC (multi version concurrency) mode
@faq_1049_li
@faq_1050_li
#Cluster mode, 2-phase commit, savepoints
@faq_1050_li
@faq_1051_li
#24/7 operation
@faq_1051_li
@faq_1052_li
#Some operations on databases larger than 500 MB may be slower than expected
@faq_1052_li
@faq_1053_li
#The optimizer may not always select the best plan
@faq_1053_li
@faq_1054_li
#Fulltext search
@faq_1054_li
@faq_1055_li
#Operations on LOBs over 2 GB
@faq_1055_p
@faq_1056_p
# Areas considered experimental are:
@faq_1056_li
@faq_1057_li
#The PostgreSQL server
@faq_1057_li
@faq_1058_li
#Multi-threading within the engine using <code>SET MULTI_THREADED=1</code>
@faq_1058_li
@faq_1059_li
#Compatibility modes for other databases (only some features are implemented)
@faq_1059_li
@faq_1060_li
#The soft reference cache (CACHE_TYPE=SOFT_LRU). It might not improve performance, and out of memory issues have been reported.
@faq_1060_p
@faq_1061_p
# Some users have reported that after a power failure, the database can sometimes not be opened because the index file is corrupt. In that case, the index file can be deleted (it is automatically re-created). To avoid this, append <code>;LOG=2</code> to the database URL. See also: <a href="grammar.html#set_log" class="notranslate">SET LOG</a>. This problem will be solved using the new 'page store' mechanism (currently beta).
@faq_1061_h3
@faq_1062_h3
#Column Names are Incorrect?
@faq_1062_p
@faq_1063_p
# For the query <code>SELECT ID AS X FROM TEST</code> the method <code>ResultSetMetaData.getColumnName()</code> returns <code>ID</code>, I expect it to return <code>X</code>. What's wrong?
@faq_1063_p
@faq_1064_p
# This is not a bug. According the the JDBC specification, the method <code>ResultSetMetaData.getColumnName()</code> should return the name of the column and not the alias name. If you need the alias name, use <a href="http://java.sun.com/javase/6/docs/api/java/sql/ResultSetMetaData.html#getColumnLabel(int)"><code>ResultSetMetaData.getColumnLabel()</code></a>. Other database don't work like this (they don't follow the JDBC specification). If you need compatibility with those databases, use the <a href="features.html#compatibility">Compatibility Mode</a>, or set the system property <a href="../javadoc/org/h2/constant/SysProperties.html#h2.aliasColumnName"><code>h2.aliasColumnName</code></a>.
@faq_1064_h3
@faq_1065_h3
#Why is Opening my Database Slow?
@faq_1065_p
@faq_1066_p
# If it takes a long time to open a database, in most cases it was not closed the last time. This is specially a problem for larger databases. To close a database, close all connections to it before the application ends, or execute the command <code>SHUTDOWN</code>. The database is also closed when the virtual machine exits normally by using a shutdown hook. However killing a Java process or calling <code>Runtime.halt</code> will prevent this. The reason why opening is slow in this situations is that indexes are re-created. If you can not guarantee the database is closed, consider using <a href="grammar.html#set_log" class="notranslate">SET LOG 2</a>.
@faq_1066_p
@faq_1067_p
# To find out what the problem is, open the database in embedded mode using the H2 Console. This will print progress information. If you have many lines with 'Creating index' it is an indication that the database was not closed the last time.
@faq_1067_p
@faq_1068_p
# Other possible reasons are: the database is very big (many GB), or contains linked tables that are slow to open.
@faq_1068_h3
@faq_1069_h3
#Is the GCJ Version Stable? Faster?
@faq_1069_p
@faq_1070_p
# The GCJ version is not as stable as the Java version. When running the regression test with the GCJ version, sometimes the application just stops at what seems to be a random point without error message. Currently, the GCJ version is also slower than when using the Sun VM. However, the startup of the GCJ version is faster than when using a VM.
@faq_1070_h3
@faq_1071_h3
このプロジェクトの翻訳方法は？
@faq_1071_p
@faq_1072_p
# For more information, see <a href="build.html#translating">Build/Translating</a>.
# SQL types are mapped to Java classes and vice-versa as in the JDBC API. For details, see <a href="datatypes.html">Data Types</a>. There are two special cases: <code>java.lang.Object</code> is mapped to <code>OTHER</code> (a serialized object). Therefore, <code>java.lang.Object</code> can not be used to match all SQL types (matching all SQL types is not supported). The second special case is <code>Object[]</code>: arrays of any class are mapped to <code>ARRAY</code>.
@features_1596_h3
接続を必要とする関数
#Functions That Require a Connection
@features_1597_p
# If the first parameter of a Java function is a <code>java.sql.Connection</code>, then the connection to database is provided. This connection does not need to be closed before returning. When calling the method from within the SQL statement, this connection parameter does not need to be (can not be) specified.
# If a function throws an exception, then the current statement is rolled back and the exception is thrown to the application.
# If a function throws an exception, then the current statement is rolled back and the exception is thrown to the application. SQLException are directly re-thrown to the calling application; all other exceptions are first converted to a SQLException.
@features_1600_h3
#Functions Returning a Result Set
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@@ -5156,7 +5174,7 @@ Sourceファイル
#What is JaQu
@jaqu_1012_p
# JaQu stands for Java Query and allows to access databases using pure Java. JaQu provides a fluent interface (or internal DSL) for building SQL statements. JaQu replaces SQL, JDBC, and persistence frameworks such as Hibernate. JaQu is something like LINQ for Java (LINQ stands for "language integrated query" and is a Microsoft .NET technology). The following JaQu code:
# JaQu stands for Java Query and allows to access databases using pure Java. JaQu provides a fluent interface (or internal DSL) to access a database. JaQu is something like LINQ for Java (LINQ stands for "language integrated query" and is a Microsoft .NET technology). The following JaQu code:
@jaqu_1013_p
# stands for the SQL statement:
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@@ -9529,15 +9547,21 @@ H2 コンソール アプリケーション
@roadmap_1438_li
#Delay creating the information schema, and share metadata columns.
@roadmap_1439_h2
@roadmap_1439_li
#TCP Server: use a nonce (number used once) to protect unencrypted channels against replay attacks.
@roadmap_1440_h2
#Not Planned
@roadmap_1440_li
@roadmap_1441_li
#HSQLDB (did) support this: select id i from test where i<0 (other databases don't). Supporting it may break compatibility.
@roadmap_1441_li
@roadmap_1442_li
#String.intern (so that Strings can be compared with ==) will not be used because some VMs have problems when used extensively.
@roadmap_1443_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.
