help.csv

# Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
# Version 1.0, and under the Eclipse Public License, Version 1.0
# (http://h2database.com/html/license.html).
# Initial Developer: H2 Group
"SECTION","TOPIC","SYNTAX","TEXT","EXAMPLE"
"Commands (DML)","SELECT","
SELECT [ TOP term ] [ DISTINCT | ALL ] selectExpression [,...]
FROM tableExpression [,...] [ WHERE expression ]
[ GROUP BY expression [,...] ] [ HAVING expression ]
[ { UNION [ ALL ] | MINUS | EXCEPT | INTERSECT } select ] [ ORDER BY order [,...] ]
[ LIMIT expression [ OFFSET expression ] [ SAMPLE_SIZE rowCountInt ] ]
[ FOR UPDATE ]
","
Selects data from a table or multiple tables.
GROUP BY groups the the result by the given expression(s).
HAVING filter rows after grouping.
ORDER BY sorts the result by the given column(s) or expression(s).
UNION combines the result of this query with the results of another query.

LIMIT limits the number of rows returned by the query (no limit if null or smaller than zero).
OFFSET specified how many rows to skip.
SAMPLE_SIZE limits the number of rows read for aggregate queries.

Multiple set operators (UNION, INTERSECT, MINUS, EXPECT) are evaluated
from left to right. For compatibility with other databases and future versions
of H2 please use parentheses.

If FOR UPDATE is specified, the tables are locked for writing. When using
MVCC, only the selected rows are locked as in an UPDATE statement.
In this case, aggregate, GROUP BY, DISTINCT queries or joins
are not allowed in this case.
","
SELECT * FROM TEST;
SELECT * FROM TEST ORDER BY NAME;
SELECT ID, COUNT(*) FROM TEST GROUP BY ID;
SELECT NAME, COUNT(*) FROM TEST GROUP BY NAME HAVING COUNT(*) > 2;
SELECT 'ID' COL, MAX(ID) AS MAX FROM TEST UNION SELECT 'NAME', MAX(NAME) FROM TEST;
SELECT * FROM TEST LIMIT 1000;
SELECT * FROM (SELECT ID, COUNT(*) FROM TEST
    GROUP BY ID UNION SELECT NULL, COUNT(*) FROM TEST)
    ORDER BY 1 NULLS LAST;
"

"Commands (DML)","INSERT","
INSERT INTO tableName
{ [ ( columnName [,...] ) ]
    { VALUES { ( { DEFAULT | expression } [,...] ) } [,...] | [ DIRECT ] [ SORTED ] select } } |
    { SET { columnName = { DEFAULT | expression } } [,...] }
","
Inserts a new row / new rows into a table.

When using DIRECT, then the results from the query are directly applied in the target table without any intermediate step.

When using SORTED, b-tree pages are split at the insertion point. This can improve performance and reduce disk usage.
","
INSERT INTO TEST VALUES(1, 'Hello')
"

"Commands (DML)","UPDATE","
UPDATE tableName [ [ AS ] newTableAlias ]
SET { columnName = { DEFAULT | expression } } [,...]
[ WHERE expression ]
","
Updates data in a table.
","
UPDATE TEST SET NAME='Hi' WHERE ID=1;
UPDATE PERSON P SET NAME=(SELECT A.NAME FROM ADDRESS A WHERE A.ID=P.ID);
"

"Commands (DML)","DELETE","
DELETE [ TOP term ] FROM tableName [ WHERE expression ] [ LIMIT term ]
","
Deletes rows form a table.
If TOP or LIMIT is specified, at most the specified number of rows are deleted (no limit if null or smaller than zero).
","
DELETE FROM TEST WHERE ID=2
"

"Commands (DML)","BACKUP","
BACKUP TO fileNameString
","
Backs up the database files to a .zip file. Objects are not locked, but
the backup is transactionally consistent because the transaction log is also copied.
Admin rights are required to execute this command.
","
BACKUP TO 'backup.zip'
"

"Commands (DML)","CALL","
CALL expression
","
Calculates a simple expression. This statement returns a result set with one row,
except if the called function returns a result set itself.
If the called function returns an array, then each element in this array is returned as a column.
","
CALL 15*25
"

"Commands (DML)","EXPLAIN","
EXPLAIN { [ PLAN FOR ] | ANALYZE } { select | insert | update | delete | merge }
","
Shows the execution plan for a statement.
When using EXPLAIN ANALYZE, the statement is actually executed, and the query plan
will include the actual row scan count for each table.
","
EXPLAIN SELECT * FROM TEST WHERE ID=1
"

"Commands (DML)","MERGE","
MERGE INTO tableName [ ( columnName [,...] ) ]
[ KEY ( columnName [,...] ) ]
{ VALUES { ( { DEFAULT | expression } [,...] ) } [,...] | select }
","
Updates existing rows, and insert rows that don't exist. If no key column is
specified, the primary key columns are used to find the row. If more than one
row per new row is affected, an exception is thrown. If the table contains an
auto-incremented key or identity column, and the row was updated, the generated
key is set to 0; otherwise it is set to the new key.
","
MERGE INTO TEST KEY(ID) VALUES(2, 'World')
"

"Commands (DML)","RUNSCRIPT","
RUNSCRIPT FROM fileNameString [ scriptCompression ]
[ CIPHER cipher PASSWORD string ] [ CHARSET charsetString ]
","
Runs a SQL script from a file. The script is a text file containing SQL
statements; each statement must end with ';'. This command can be used to
restore a database from a backup. The password must be in single quotes; it is
case sensitive and can contain spaces.

Instead of a file name, an URL may be used.
To read a stream from the classpath, use the prefix 'classpath:'.

The compression algorithm must match the one used when creating the script. When
using encryption, only DEFLATE and LZF are supported (LZF is faster but uses more space).
Instead of a file, an URL may be used.

Admin rights are required to execute this command.
","
RUNSCRIPT FROM 'backup.sql'
"

"Commands (DML)","SCRIPT","
SCRIPT [ SIMPLE ] [ NODATA ] [ NOPASSWORDS ] [ NOSETTINGS ]
[ DROP ] [ BLOCKSIZE blockSizeInt ]
[ TO fileNameString [ scriptCompression ]
    [ CIPHER cipher PASSWORD string ] ]
[ CHARSET charsetString ]
","
Creates a SQL script from the database.

SIMPLE does not use multi-row insert statements.
NODATA will not emit INSERT statements.
If the DROP option is specified, drop statements are created for tables, views,
and sequences. If the block size is set, CLOB and BLOB values larger than this
size are split into separate blocks.

If no file name is specified, the
script is returned as a result set. This command can be used to create a backup
of the database. For long term storage, it is more portable than copying the
database files.

If a file name is specified, then the whole
script (including insert statements) is written to this file, and a result set
without the insert statements is returned. When using encryption, only DEFLATE
and LZF are supported (LZF is faster but uses more space).

The password must be in single quotes; it is case sensitive and can contain spaces.

This command locks objects while it is running.
","
SCRIPT NODATA
"

"Commands (DML)","SHOW","
SHOW { SCHEMAS | TABLES [ FROM schemaName ] |
    COLUMNS FROM tableName [ FROM schemaName ] }
","
Lists the schemas, tables, or the columns of a table.
","
SHOW TABLES
"

"Commands (DDL)","ALTER INDEX RENAME","
ALTER INDEX indexName RENAME TO newIndexName
","
Renames an index.
This command commits an open transaction.
","
ALTER INDEX IDXNAME RENAME TO IDX_TEST_NAME
"

"Commands (DDL)","ALTER SCHEMA RENAME","
ALTER SCHEMA schema RENAME TO newSchemaName
","
Renames a schema.
This command commits an open transaction.
","
ALTER SCHEMA TEST RENAME TO PRODUCTION
"

"Commands (DDL)","ALTER SEQUENCE","
ALTER SEQUENCE sequenceName [ RESTART WITH long ] [ INCREMENT BY long ]
","
Changes the next value and the increment of a sequence.
This command does not commit the current transaction; however the new value is used by other
transactions immediately, and rolling back this command has no effect.
","
ALTER SEQUENCE SEQ_ID RESTART WITH 1000
"

"Commands (DDL)","ALTER TABLE ADD","
ALTER TABLE tableName ADD [ IF NOT EXISTS ] name dataType [ DEFAULT expression ]
[ [ NOT ] NULL ] [ AUTO_INCREMENT | IDENTITY ] [ BEFORE columnName ]
","
Adds a new column to a table.
This command commits an open transaction.
","
ALTER TABLE TEST ADD CREATEDATE TIMESTAMP
"

"Commands (DDL)","ALTER TABLE ADD CONSTRAINT","
ALTER TABLE tableName ADD constraint [ CHECK | NOCHECK ]
","
Adds a constraint to a table. If NOCHECK is specified, existing rows are not
checked for consistency (the default is to check consistency for existing rows).
The required indexes are automatically created if they don't exist yet.
It is not possible to disable checking for unique constraints.
This command commits an open transaction.
","
ALTER TABLE TEST ADD CONSTRAINT NAME_UNIQUE UNIQUE(NAME)
"

"Commands (DDL)","ALTER TABLE ALTER","
ALTER TABLE tableName ALTER COLUMN columnName
{ { dataType [ DEFAULT expression ] [ [ NOT ] NULL ] [ AUTO_INCREMENT | IDENTITY ] }
    | { RENAME TO name }
    | { RESTART WITH long }
    | { SELECTIVITY int }
    | { SET DEFAULT expression }
    | { SET NULL }
    | { SET NOT NULL } }
","
Changes the data type of a column, rename a column,
change the identity value, or change the selectivity.

Changing the data type fails if the data can not be converted.

RESTART changes the next value of an auto increment column.
The column must already be an auto increment column.
For RESTART, the same transactional rules as for ALTER SEQUENCE apply.

SELECTIVITY sets the selectivity (1-100) for a column.
Setting the selectivity to 0 means the default value.
Selectivity is used by the cost based optimizer to calculate the estimated cost of an index.
Selectivity 100 means values are unique, 10 means every distinct value appears 10 times on average.

SET DEFAULT changes the default value of a column.

SET NULL sets a column to allow NULL. The row may not be part of a primary key.
Single column indexes on this column are dropped.

SET NOT NULL sets a column to not allow NULL. Rows may not contains NULL in this column.

This command commits an open transaction.
","
ALTER TABLE TEST ALTER COLUMN NAME CLOB;
ALTER TABLE TEST ALTER COLUMN NAME RENAME TO TEXT;
ALTER TABLE TEST ALTER COLUMN ID RESTART WITH 10000;
ALTER TABLE TEST ALTER COLUMN NAME SELECTIVITY 100;
ALTER TABLE TEST ALTER COLUMN NAME SET DEFAULT '';
ALTER TABLE TEST ALTER COLUMN NAME SET NOT NULL;
ALTER TABLE TEST ALTER COLUMN NAME SET NULL;
"

"Commands (DDL)","ALTER TABLE DROP COLUMN","
ALTER TABLE tableName DROP COLUMN columnName
","
Removes a column from a table.
This command commits an open transaction.
","
ALTER TABLE TEST DROP COLUMN NAME
"

"Commands (DDL)","ALTER TABLE DROP CONSTRAINT","
ALTER TABLE tableName DROP { CONSTRAINT [ IF EXISTS ] constraintName | PRIMARY KEY }
","
Removes a constraint or a primary key from a table.
This command commits an open transaction.
","
ALTER TABLE TEST DROP CONSTRAINT UNIQUE_NAME
"

"Commands (DDL)","ALTER TABLE SET","
ALTER TABLE tableName SET REFERENTIAL_INTEGRITY
    { FALSE | TRUE [ CHECK | NOCHECK ] }
","
Disables or enables referential integrity checking for a table. This command can
be used inside a transaction. Enabling referential integrity does not check
existing data, except if CHECK is specified. Use SET REFERENTIAL_INTEGRITY to
disable it for all tables; the global flag and the flag for each table are
independent.

This command commits an open transaction.
","
ALTER TABLE TEST SET REFERENTIAL_INTEGRITY FALSE
"

"Commands (DDL)","ALTER TABLE RENAME","
ALTER TABLE tableName RENAME TO newName
","
Renames a table.
This command commits an open transaction.
","
ALTER TABLE TEST RENAME TO MY_DATA
"

"Commands (DDL)","ALTER USER ADMIN","
ALTER USER userName ADMIN { TRUE | FALSE }
","
Switches the admin flag of a user on or off.

Only unquoted or uppercase user names are allowed.
Admin rights are required to execute this command.
This command commits an open transaction.
","
ALTER USER TOM ADMIN TRUE
"

"Commands (DDL)","ALTER USER RENAME","
ALTER USER userName RENAME TO newUserName
","
Renames a user.
After renaming a user, the password becomes invalid and needs to be changed as well.

Only unquoted or uppercase user names are allowed.
Admin rights are required to execute this command.
This command commits an open transaction.
","
ALTER USER TOM RENAME TO THOMAS
"

"Commands (DDL)","ALTER USER SET PASSWORD","
ALTER USER userName SET { PASSWORD string | SALT bytes HASH bytes }
","
Changes the password of a user.
Only unquoted or uppercase user names are allowed.
The password must be enclosed in single quotes. It is case sensitive
and can contain spaces. The salt and hash values are hex strings.

Admin rights are required to execute this command.
This command commits an open transaction.
","
ALTER USER SA SET PASSWORD 'rioyxlgt'
"

"Commands (DDL)","ALTER VIEW","
ALTER VIEW viewName RECOMPILE
","
Recompiles a view after the underlying tables have been changed or created.
This command is used for views created using CREATE FORCE VIEW.
This command commits an open transaction.
","
ALTER VIEW ADDRESS_VIEW RECOMPILE
"

"Commands (DDL)","ANALYZE","
ANALYZE [ SAMPLE_SIZE rowCountInt ]
","
Updates the selectivity statistics of all tables. The selectivity is used by the
cost based optimizer to select the best index for a given query. If no sample
size is set, up to 10000 rows per table are read. The value 0 means all rows are
read. The selectivity can be set manually using ALTER TABLE ALTER COLUMN
SELECTIVITY. Manual values are overwritten by this statement. The selectivity is
available in the INFORMATION_SCHEMA.COLUMNS table.

This command commits an open transaction.
","
ANALYZE SAMPLE_SIZE 1000
"

"Commands (DDL)","COMMENT","
COMMENT ON
{ { COLUMN [ schemaName. ] tableName.columnName }
    | { { TABLE | VIEW | CONSTANT | CONSTRAINT | ALIAS | INDEX | ROLE
    | SCHEMA | SEQUENCE | TRIGGER | USER | DOMAIN } [ schemaName. ] objectName } }
IS expression
","
Sets the comment of a database object. Use NULL to remove the comment.

Admin rights are required to execute this command.
This command commits an open transaction.
","
COMMENT ON TABLE TEST IS 'Table used for testing'
"

"Commands (DDL)","CREATE AGGREGATE","
CREATE AGGREGATE [ IF NOT EXISTS ] newAggregateName FOR className
","
Creates a new user-defined aggregate function. The method name must be the full
qualified class name. The class must implement the interface
""org.h2.api.AggregateFunction"".

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE AGGREGATE MEDIAN FOR ""com.acme.db.Median""
"

"Commands (DDL)","CREATE ALIAS","
CREATE ALIAS [ IF NOT EXISTS ] newFunctionAliasName [ DETERMINISTIC ]
{ FOR classAndMethodName | AS sourceCodeString }
","
Creates a new function alias. Deterministic functions must always return the
same value for the same parameters. The result of such functions is cached if possible.

The method name must be the full qualified class and method name,
and may optionally include the parameter classes as in
""java.lang.Integer.parseInt(java.lang.String, int)"". The class and the method
must both be public, and the method must be static. The class must be available
in the classpath of the database engine (when using the server mode,
it must be in the classpath of the server).

When defining a function alias with source code, the Sun ""javac"" is compiler
is used if the file ""tools.jar"" is in the classpath. If not, ""javac"" is run as a separate process.
Only the source code is stored in the database; the class is compiled each time
the database is re-opened. Source code is usually passed
as dollar quoted text to avoid escaping problems. If import statements are used,
then the tag @CODE must be added before the method.

If the method throws an SQLException, it is directly re-thrown to the calling application;
all other exceptions are first converted to a SQLException.

If the first parameter of the Java function is a ""java.sql.Connection"", then a
connection to the database is provided. This connection must not be closed.
If the class contains multiple methods with the given name but different
parameter count, all methods are mapped.

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE ALIAS MY_SQRT FOR ""java.lang.Math.sqrt"";
CREATE ALIAS GET_SYSTEM_PROPERTY FOR ""java.lang.System.getProperty"";
CALL GET_SYSTEM_PROPERTY('java.class.path');
CALL GET_SYSTEM_PROPERTY('com.acme.test', 'true');
CREATE ALIAS REVERSE AS $$ String reverse(String s) { return new StringBuilder(s).reverse().toString(); } $$;
CALL REVERSE('Test');
"

"Commands (DDL)","CREATE CONSTANT","
CREATE CONSTANT [ IF NOT EXISTS ] newConstantName VALUE expression
","
Creates a new constant.
This command commits an open transaction.
","
CREATE CONSTANT ONE VALUE 1
"

"Commands (DDL)","CREATE DOMAIN","
CREATE DOMAIN [ IF NOT EXISTS ] newDomainName AS dataType
[ DEFAULT expression ] [ [ NOT ] NULL ] [ SELECTIVITY selectivity ]
[ CHECK condition ]
","
Creates a new data type (domain). The check condition must evaluate to true or
to NULL (to prevent NULL, use ""NOT NULL""). In the condition, the term VALUE refers
to the value being tested.

Domains are usable within the whole database. They can not be created in a specific schema.

This command commits an open transaction.
","
CREATE DOMAIN EMAIL AS VARCHAR(255) CHECK (POSITION('@', VALUE) > 1)
"

"Commands (DDL)","CREATE INDEX","
CREATE { [ UNIQUE ] [ HASH ] INDEX [ IF NOT EXISTS ] newIndexName
    | PRIMARY KEY [ HASH ] }
ON tableName ( indexColumn [,...] )
","
Creates a new index.
This command commits an open transaction.

Hash indexes are meant for in-memory databases and memory tables (CREATE MEMORY TABLE).
For other tables, or if the index contains multiple columns, the HASH keyword is ignored.
Hash indexes can only test for equality, and do not support range queries (similar to a hash table).
Non-unique keys are supported.
","
CREATE INDEX IDXNAME ON TEST(NAME)
"

"Commands (DDL)","CREATE LINKED TABLE","
CREATE [ [ GLOBAL | LOCAL ] TEMPORARY ] LINKED TABLE [ IF NOT EXISTS ]
name ( driverString, urlString, userString, passwordString,
[ originalSchemaString, ] originalTableString ) [ EMIT UPDATES | READONLY ]
","
Creates a table link to an external table. The driver name may be empty if the
driver is already loaded. If the schema name is not set, only one table with
that name may exist in the target database.

Usually, for update statements, the old rows are deleted first and then the new
rows are inserted. It is possible to emit update statements (except on
rollback), however in this case multi-row unique key updates may not always
work. Linked tables to the same database share one connection.

If a query is used instead of the original table name, the table is read only.
Queries must be enclosed in parenthesis: ""(SELECT * FROM ORDERS)"".

To use JNDI to get the connection, the driver class must be a
javax.naming.Context (for example ""javax.naming.InitialContext""), and the URL must
be the resource name (for example ""java:comp/env/jdbc/Test"").

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE LINKED TABLE LINK('org.h2.Driver', 'jdbc:h2:test2', 'sa', 'sa', 'TEST');
CREATE LINKED TABLE LINK('', 'jdbc:h2:test2', 'sa', 'sa',
    '(SELECT * FROM TEST WHERE ID>0)');
CREATE LINKED TABLE LINK('javax.naming.InitialContext',
    'java:comp/env/jdbc/Test', NULL, NULL, '(SELECT * FROM TEST WHERE ID>0)');
"

"Commands (DDL)","CREATE ROLE","
CREATE ROLE [ IF NOT EXISTS ] newRoleName
","
Creates a new role.
This command commits an open transaction.
","
CREATE ROLE READONLY
"

"Commands (DDL)","CREATE SCHEMA","
CREATE SCHEMA [ IF NOT EXISTS ] name [ AUTHORIZATION ownerUserName ]
","
Creates a new schema. If no owner is specified, the current user is used. The
user that executes the command must have admin rights, as well as the owner.
Specifying the owner currently has no effect.

This command commits an open transaction.
","
CREATE SCHEMA TEST_SCHEMA AUTHORIZATION SA
"

"Commands (DDL)","CREATE SEQUENCE","
CREATE SEQUENCE [ IF NOT EXISTS ] newSequenceName [ START WITH long ]
[ INCREMENT BY long ] [ CACHE long ]
","
Creates a new sequence. The data type of a sequence is BIGINT. Used values are
never re-used, even when the transaction is rolled back. The cache is the number
of pre-allocated numbers. If the system crashes without closing the database, at
most this many numbers are lost. The default cache size is 32.

This command commits an open transaction.
","
CREATE SEQUENCE SEQ_ID
"

"Commands (DDL)","CREATE TABLE","
CREATE [ CACHED | MEMORY ] [ TEMP | [ GLOBAL | LOCAL ] TEMPORARY ]
TABLE [ IF NOT EXISTS ] name
{ { ( { columnDefinition | constraint } [,...] ) [ AS select ] }
    | { AS select } }
[ ENGINE tableEngineName ] [ TRANSACTIONAL ] [ NOT PERSISTENT ]
","
Creates a new table.

Cached tables (the default for regular tables) are persistent,
and the number of rows is not limited by the main memory.
Memory tables (the default for temporary tables) are persistent,
but the index data is kept in main memory,
that means memory tables should not get too large.

Temporary tables are deleted when closing or opening a database.
Temporary tables can be global (accessible by all connections)
or local (only accessible by the current connection).
The default for temporary tables is global.
Indexes of temporary tables are kept fully in main memory,
unless the temporary table is created using CREATE CACHED TABLE.

The ENGINE option is only required when custom table implementations are used.
The table engine class must implement the interface ""org.h2.api.TableEngine"".

Tables with the NOT PERSISTENT modifier are kept fully in memory, and all
rows are lost when the database is closed.

This command commits an open transaction, except when using
TRANSACTIONAL (only supported for temporary tables).
","
CREATE TABLE TEST(ID INT PRIMARY KEY, NAME VARCHAR(255))
"

"Commands (DDL)","CREATE TRIGGER","
CREATE TRIGGER [ IF NOT EXISTS ] newTriggerName { BEFORE | AFTER | INSTEAD OF }
{ INSERT | UPDATE | DELETE | SELECT | ROLLBACK } [,...] ON tableName [ FOR EACH ROW ]
[ QUEUE int ] [ NOWAIT ] CALL triggeredClassName
","
Creates a new trigger. The trigger class must be public. Inner classes are not supported.
The class must be available in the classpath of the
database engine (when using the server mode, it must be in the classpath of the server).

BEFORE triggers are called after data conversion is made, default values are set,
null and length constraint checks have been made;
but before other constraints have been checked.
If there are multiple triggers, the order in which they are called is undefined.

Only row based AFTER trigger can be called on rollback.
Exceptions that occur within such triggers are ignored.

INSTEAD OF triggers are implicitly row based and behave like BEFORE triggers.
Only the first such trigger is called. Such triggers on views are supported.
They can be used to make views updatable.

The MERGE statement will call both INSERT and UPDATE triggers.
Not supported are SELECT triggers with the option FOR EACH ROW,
and AFTER SELECT triggers.

Committing or rolling back a transaction within a trigger is not allowed, except for SELECT triggers.

The trigger need to be created in the same schema as the table.
The schema name does not need to be specified when creating the trigger.

This command commits an open transaction.
","
CREATE TRIGGER TRIG_INS BEFORE INSERT ON TEST FOR EACH ROW CALL ""MyTrigger""
"
"Commands (DDL)","CREATE USER","
CREATE USER [ IF NOT EXISTS ] newUserName
{ PASSWORD string | SALT bytes HASH bytes } [ ADMIN ]
","
Creates a new user. For compatibility, only unquoted or uppercase user names are allowed.
The password must be in single quotes. It is case sensitive and can contain spaces.
The salt and hash values are hex strings.

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE USER GUEST PASSWORD 'abc'
"

"Commands (DDL)","CREATE VIEW","
CREATE [ OR REPLACE ] [ FORCE ] VIEW [ IF NOT EXISTS ] newViewName
[ ( columnName [,...] ) ] AS select
","
Creates a new view. If the force option is used, then the view is created even
if the underlying table(s) don't exist.

If the OR REPLACE clause is used an existing view will be replaced, and any
dependent views will not need to be recreated. If dependent views will become
invalid as a result of the change an error will be generated, but this error
can be ignored if the FORCE clause is also used.

Views are not updatable except when using 'instead of' triggers.

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE VIEW TEST_VIEW AS SELECT * FROM TEST WHERE ID < 100
"

"Commands (DDL)","DROP AGGREGATE","
DROP AGGREGATE [ IF EXISTS ] aggregateName
","
Drops an existing user-defined aggregate function.

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE AGGREGATE MEDIAN
"

"Commands (DDL)","DROP ALIAS","
DROP ALIAS [ IF EXISTS ] existingFunctionAliasName
","
Drops an existing function alias.

Admin rights are required to execute this command.
This command commits an open transaction.
","
CREATE ALIAS MY_SQRT
"

"Commands (DDL)","DROP ALL OBJECTS","
DROP ALL OBJECTS [ DELETE FILES ]
","
Drops all existing views, tables, sequences, schemas, function aliases, roles,
user-defined aggregate functions, domains, and users (except the current user).
If DELETE FILES is specified, the database files will be removed when the last
user disconnects from the database. Warning: this command can not be rolled
back.

Admin rights are required to execute this command.
","
DROP ALL OBJECTS
"

"Commands (DDL)","DROP CONSTANT","
DROP CONSTANT [ IF EXISTS ] constantName
","
Drops a constant.
This command commits an open transaction.
","
DROP CONSTANT ONE
"

"Commands (DDL)","DROP DOMAIN","
DROP DOMAIN [ IF EXISTS ] domainName
","
Drops a data type (domain).
This command commits an open transaction.
","
DROP DOMAIN EMAIL
"

"Commands (DDL)","DROP INDEX","
DROP INDEX [ IF EXISTS ] indexName
","
Drops an index.
This command commits an open transaction.
","
DROP INDEX IF EXISTS IDXNAME
"

"Commands (DDL)","DROP ROLE","
DROP ROLE [ IF EXISTS ] roleName
","
Drops a role.
This command commits an open transaction.
","
DROP ROLE READONLY
"

"Commands (DDL)","DROP SCHEMA","
DROP SCHEMA [ IF EXISTS ] schemaName
","
Drops a schema.
This command commits an open transaction.
","
DROP SCHEMA TEST_SCHEMA
"

"Commands (DDL)","DROP SEQUENCE","
DROP SEQUENCE [ IF EXISTS ] sequenceName
","
Drops a sequence.
This command commits an open transaction.
","
DROP SEQUENCE SEQ_ID
"

"Commands (DDL)","DROP TABLE","
DROP TABLE [ IF EXISTS ] tableName [,...] [ CASCADE | RESTRICT ]
","
Drops an existing table, or a list of tables.
All dependent views are dropped as well if the CASCADE clause is used (the default).
The command will fail if dependent views exist and the RESTRICT clause is used.
This command commits an open transaction.
","
DROP TABLE TEST
"

"Commands (DDL)","DROP TRIGGER","
DROP TRIGGER [ IF EXISTS ] triggerName
","
Drops an existing trigger.
This command commits an open transaction.
","
DROP TRIGGER TRIG_INS
"

"Commands (DDL)","DROP USER","
DROP USER [ IF EXISTS ] userName
","
Drops a user. The current user cannot be dropped.
For compatibility, only unquoted or uppercase user names are allowed.

Admin rights are required to execute this command.
This command commits an open transaction.
","
DROP USER TOM
"

"Commands (DDL)","DROP VIEW","
DROP VIEW [ IF EXISTS ] viewName [ RESTRICT | CASCADE ]
","
Drops an existing view.
All dependent views are dropped as well if the CASCADE clause is used (the default).
The command will fail if dependent views exist and the RESTRICT clause is used.
This command commits an open transaction.
","
DROP VIEW TEST_VIEW
"

"Commands (DDL)","TRUNCATE TABLE","
TRUNCATE TABLE tableName
","
Removes all rows from a table.
Unlike DELETE FROM without where clause, this command can not be rolled back.
This command is faster than DELETE without where clause.
Only regular data tables without foreign key constraints can be truncated
(except if referential integrity is disabled for this database or for this table).
Linked tables can't be truncated.

This command commits an open transaction.
","
TRUNCATE TABLE TEST
"

"Commands (Other)","CHECKPOINT","
CHECKPOINT
","
Flushes the data to disk and switches to a new transaction log if possible.

Admin rights are required to execute this command.
","
CHECKPOINT
"

"Commands (Other)","CHECKPOINT SYNC","
CHECKPOINT SYNC
","
Flushes the data to disk and and forces all system buffers be written
to the underlying device.

Admin rights are required to execute this command.
","
CHECKPOINT SYNC
"

"Commands (Other)","COMMIT","
COMMIT [ WORK ]
","
Commits a transaction.
","
COMMIT
"

"Commands (Other)","COMMIT TRANSACTION","
COMMIT TRANSACTION transactionName
","
Sets the resolution of an in-doubt transaction to 'commit'.

Admin rights are required to execute this command.
This command is part of the 2-phase-commit protocol.
","
COMMIT TRANSACTION XID_TEST
"

"Commands (Other)","GRANT RIGHT","
GRANT { SELECT | INSERT | UPDATE | DELETE | ALL } [,...] ON
tableName [,...] TO { PUBLIC | userName | roleName }
","
Grants rights for a table to a user or role.

Admin rights are required to execute this command.
This command commits an open transaction.
","
GRANT SELECT ON TEST TO READONLY
"

"Commands (Other)","GRANT ROLE","
GRANT roleName TO { PUBLIC | userName | roleName }
","
Grants a role to a user or role.

Admin rights are required to execute this command.
This command commits an open transaction.
","
GRANT READONLY TO PUBLIC
"

"Commands (Other)","HELP","
HELP [ anything [...] ]
","
Displays the help pages of SQL commands or keywords.
","
HELP SELECT
"

"Commands (Other)","PREPARE COMMIT","
PREPARE COMMIT newTransactionName
","
Prepares committing a transaction.
This command is part of the 2-phase-commit protocol.
","
PREPARE COMMIT XID_TEST
"

"Commands (Other)","REVOKE RIGHT","
REVOKE { SELECT | INSERT | UPDATE | DELETE | ALL } [,...] ON
tableName [,...] FROM { PUBLIC | userName | roleName }
","
Removes rights for a table from a user or role.

Admin rights are required to execute this command.
This command commits an open transaction.
","
REVOKE SELECT ON TEST FROM READONLY
"

"Commands (Other)","REVOKE ROLE","
REVOKE roleName FROM { PUBLIC | userName | roleName }
","
Removes a role from a user or role.

Admin rights are required to execute this command.
This command commits an open transaction.
","
REVOKE READONLY FROM TOM
"

"Commands (Other)","ROLLBACK","
ROLLBACK [ TO SAVEPOINT savepointName ]
","
Rolls back a transaction. If a savepoint name is used, the transaction is only
rolled back to the specified savepoint.
","
ROLLBACK
"

"Commands (Other)","ROLLBACK TRANSACTION","
ROLLBACK TRANSACTION transactionName
","
Sets the resolution of an in-doubt transaction to 'rollback'.

Admin rights are required to execute this command.
This command is part of the 2-phase-commit protocol.
","
ROLLBACK TRANSACTION XID_TEST
"

"Commands (Other)","SAVEPOINT","
SAVEPOINT savepointName
","
Create a new savepoint. See also ROLLBACK.
Savepoints are only valid until the transaction is committed or rolled back.
","
SAVEPOINT HALF_DONE
"

"Commands (Other)","SET @","
SET @variableName [ = ] expression
","
Updates a user-defined variable.
This command does not commit a transaction, and rollback does not affect it.
","
SET @TOTAL=0
"

"Commands (Other)","SET ALLOW_LITERALS","
SET ALLOW_LITERALS { NONE | ALL | NUMBERS }
","
This setting can help solve the SQL injection problem. By default, text and
number literals are allowed in SQL statements. However, this enables SQL
injection if the application dynamically builds SQL statements. SQL injection is
not possible if user data is set using parameters ('?').

NONE means literals of any kind are not allowed, only parameters and constants
are allowed. NUMBERS mean only numerical and boolean literals are allowed. ALL
means all literals are allowed (default).

See also CREATE CONSTANT.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
This setting can be appended to the database URL: ""jdbc:h2:test;ALLOW_LITERALS=NONE""
","
SET ALLOW_LITERALS NONE
"

"Commands (Other)","SET AUTOCOMMIT","
SET AUTOCOMMIT { TRUE | ON | FALSE | OFF }
","
Switches auto commit on or off.
This setting can be appended to the database URL: ""jdbc:h2:test;AUTOCOMMIT=OFF"" -
however this will not work as expected when using a connection pool
(the connection pool manager will re-enable autocommit when returning
the connection to the pool, so autocommit will only be disabled the first
time the connection is used.
","
SET AUTOCOMMIT OFF
"

"Commands (Other)","SET CACHE_SIZE","
SET CACHE_SIZE int
","
Sets the size of the cache in KB (each KB being 1024 bytes) for the current database.
The default value is 16384 (16 MB). The value is rounded to the next higher power of two.
Depending on the virtual machine, the actual memory required may be higher.

This setting is persistent and affects all connections as there is only one cache per database.
Using a very small value (specially 0) will reduce performance a lot.
This setting only affects the database engine (the server in a client/server environment).
It has no effect for in-memory databases.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
This setting can be appended to the database URL: ""jdbc:h2:test;CACHE_SIZE=8192""
","
SET CACHE_SIZE 8192
"

"Commands (Other)","SET CLUSTER","
SET CLUSTER serverListString
","
This command should not be used directly by an application, the statement is
executed automatically by the system. The behavior may change in future
releases. Sets the cluster server list. An empty string switches off the cluster
mode. Switching on the cluster mode requires admin rights, but any user can
switch it off (this is automatically done when the client detects the other
server is not responding).

This command is effective immediately, but does not commit an open transaction.
","
SET CLUSTER ''
"

"Commands (Other)","SET COLLATION","
SET [ DATABASE ] COLLATION
{ OFF | collationName [ STRENGTH { PRIMARY | SECONDARY | TERTIARY | IDENTICAL } ] }
","
Sets the collation used for comparing strings.
This command can only be executed if there are no tables defined.
See ""java.text.Collator"" for details about the supported collations and the STRENGTH.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET COLLATION ENGLISH
"

"Commands (Other)","SET COMPRESS_LOB","
SET COMPRESS_LOB { NO | LZF | DEFLATE }
","
Sets the compression algorithm for BLOB and CLOB data. Compression is usually
slower, but needs less disk space. LZF is faster but uses more space.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET COMPRESS_LOB LZF
"

"Commands (Other)","SET DATABASE_EVENT_LISTENER","
SET DATABASE_EVENT_LISTENER classNameString
","
Sets the event listener class. An empty string ('') means no listener should be
used. This setting is not persistent.

Admin rights are required to execute this command, except if it is set when
opening the database (in this case it is reset just after opening the database).
This setting can be appended to the database URL: ""jdbc:h2:test;DATABASE_EVENT_LISTENER='sample.MyListener'""
","
SET DATABASE_EVENT_LISTENER 'sample.MyListener'
"

"Commands (Other)","SET DB_CLOSE_DELAY","
SET DB_CLOSE_DELAY int
","
Sets the delay for closing a database if all connections are closed. The value
-1 means the database is never closed until the close delay is set to some other
value or SHUTDOWN is called. The value 0 means no delay (default; the database
is closed if the last connection to it is closed). Values 1 and larger mean the
number of seconds the database is left open after closing the last connection.

If the application exits normally or System.exit is called, the database is
closed immediately, even if a delay is set.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
This setting can be appended to the database URL: ""jdbc:h2:test;DB_CLOSE_DELAY=-1""
","
SET DB_CLOSE_DELAY -1
"

"Commands (Other)","SET DEFAULT_LOCK_TIMEOUT","
SET DEFAULT LOCK_TIMEOUT int
","
Sets the default lock timeout (in milliseconds) in this database that is used
for the new sessions. The default value for this setting is 1000 (one second).

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET DEFAULT_LOCK_TIMEOUT 5000
"

"Commands (Other)","SET DEFAULT_TABLE_TYPE","
SET DEFAULT_TABLE_TYPE { MEMORY | CACHED }
","
Sets the default table storage type that is used when creating new tables.
Memory tables are kept fully in the main memory (including indexes), however
the data is still stored in the database file. The size of memory tables is
limited by the memory. The default is CACHED.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
It has no effect for in-memory databases.
","
SET DEFAULT_TABLE_TYPE MEMORY
"

"Commands (Other)","SET EXCLUSIVE","
SET EXCLUSIVE { 0 | 1 | 2 }
","
Switched the database to exclusive mode (1, 2) and back to normal mode (0).

In exclusive mode, new connections are rejected, and operations by
other connections are paused until the exclusive mode is disabled.
When using the value 1, existing connections stay open.
When using the value 2, all existing connections are closed
(and current transactions are rolled back) except the connection
that executes SET EXCLUSIVE.
Only the connection that set the exclusive mode can disable it.
When the connection is closed, it is automatically disabled.

Admin rights are required to execute this command.
This command commits an open transaction.
","
SET EXCLUSIVE 1
"

"Commands (Other)","SET IGNORECASE","
SET IGNORECASE { TRUE | FALSE }
","
If IGNORECASE is enabled, text columns in newly created tables will be
case-insensitive. Already existing tables are not affected. The effect of
case-insensitive columns is similar to using a collation with strength PRIMARY.
Case-insensitive columns are compared faster than when using a collation.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET IGNORECASE TRUE
"

"Commands (Other)","SET LOG","
SET LOG int
","
Sets the transaction log mode. The values 0, 1, and 2 are supported, the default is 2.
This setting affects all connections.

LOG 0 means the transaction log is disabled completely. It is the fastest mode,
but also the most dangerous: if the process is killed while the database is open in this mode,
the data might be lost. It must only be used if this is not a problem, for example when
initially loading a database, or when running tests.

LOG 1 means the transaction log is enabled, but FileDescriptor.sync is disabled.
This setting is about half as fast as with LOG 0. This setting is useful if no protection
against power failure is required, but the data must be protected against killing the process.

LOG 2 (the default) means the transaction log is enabled, and FileDescriptor.sync is called
for each checkpoint. This setting is about half as fast as LOG 1. Depending on the
file system, this will also protect against power failure in the majority if cases.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is not persistent.
This setting can be appended to the database URL: ""jdbc:h2:test;LOG=0""
","
SET LOG 1
"

"Commands (Other)","SET LOCK_MODE","
SET LOCK_MODE int
","
Sets the lock mode. The values 0, 1, 2, and 3 are supported. The default is 3
(READ_COMMITTED). This setting affects all connections.

The value 0 means no locking (should only be used for testing; also known as
READ_UNCOMMITTED). Please note that using SET LOCK_MODE 0 while at the same time
using multiple connections may result in inconsistent transactions.

The value 1 means table level locking (also known as SERIALIZABLE).

The value 2 means table level locking with garbage collection (if the
application does not close all connections).

The value 3 means table level locking, but read locks are released immediately
(default; also known as READ_COMMITTED).

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
This setting can be appended to the database URL: ""jdbc:h2:test;LOCK_MODE=3""
","
SET LOCK_MODE 1
"

"Commands (Other)","SET LOCK_TIMEOUT","
SET LOCK_TIMEOUT int
","
Sets the lock timeout (in milliseconds) for the current session. The default
value for this setting is 1000 (one second).

This command does not commit a transaction, and rollback does not affect it.
This setting can be appended to the database URL: ""jdbc:h2:test;LOCK_TIMEOUT=10000""
","
SET LOCK_TIMEOUT 1000
"

"Commands (Other)","SET MAX_LENGTH_INPLACE_LOB","
SET MAX_LENGTH_INPLACE_LOB int
","
Sets the maximum size of an in-place LOB object. LOB objects larger that this
size are stored in a separate file, otherwise stored directly in the database
(in-place). The default max size is 1024.
This setting has no effect for in-memory databases.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET MAX_LENGTH_INPLACE_LOB 128
"

"Commands (Other)","SET MAX_LOG_SIZE","
SET MAX_LOG_SIZE int
","
Sets the maximum size of the transaction log, in megabytes. If the log exceeds the
limit, a new stream is created. Old streams (that are not used for recovery) are
freed automatically. The default max size is 16 MB.
This setting has no effect for in-memory databases.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
","
SET MAX_LOG_SIZE 2
"

"Commands (Other)","SET MAX_MEMORY_ROWS","
SET MAX_MEMORY_ROWS int
","
The maximum number of rows in a result set that are kept in-memory. If more rows
are read, then the rows are buffered to disk. The default value is 10000.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
It has no effect for in-memory databases.
","
SET MAX_MEMORY_ROWS 1000
"

"Commands (Other)","SET MAX_MEMORY_UNDO","
SET MAX_MEMORY_UNDO int
","
The maximum number of undo records per a session that are kept in-memory.
If a transaction is larger, the records are buffered to disk.
The default value is 50000.
Changes to tables without a primary key can not be buffered to disk.
This setting is not supported when using multi-version concurrency.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting is persistent.
It has no effect for in-memory databases.
","
SET MAX_MEMORY_UNDO 1000
"

"Commands (Other)","SET MAX_OPERATION_MEMORY","
SET MAX_OPERATION_MEMORY int
","
Sets the maximum memory used for large operations (delete and insert), in bytes.
Operations that use more memory are buffered to disk, slowing down the
operation. The default max size is 100000. 0 means no limit.

This setting is not persistent.
Admin rights are required to execute this command.
It has no effect for in-memory databases.
This setting can be appended to the database URL: ""jdbc:h2:test;MAX_OPERATION_MEMORY=10000""
","
SET MAX_OPERATION_MEMORY 0
"

"Commands (Other)","SET MODE","
SET MODE { REGULAR | DB2 | DERBY | HSQLDB | MSSQLSERVER | MYSQL | ORACLE | POSTGRESQL }
","
Changes to another database compatibility mode. For details, see Compatibility
Modes in the feature section.

This setting is not persistent.
Admin rights are required to execute this command.
This command commits an open transaction.
This setting can be appended to the database URL: ""jdbc:h2:test;MODE=MYSQL""
","
SET MODE HSQLDB
"

"Commands (Other)","SET MULTI_THREADED","
SET MULTI_THREADED { 0 | 1 }
","
Enabled (1) or disabled (0) multi-threading inside the database engine. By
default, this setting is disabled. Currently, enabling this is experimental
only.

This is a global setting, which means it is not possible to open multiple databases with different modes at the same time in the same virtual machine.
This setting is not persistent, however the value is kept until the virtual machine exits or it is changed.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting can be appended to the database URL: ""jdbc:h2:test;MULTI_THREADED=1""
","
SET MULTI_THREADED 1
"

"Commands (Other)","SET OPTIMIZE_REUSE_RESULTS","
SET OPTIMIZE_REUSE_RESULTS { 0 | 1 }
","
Enabled (1) or disabled (0) the result reuse optimization. If enabled,
subqueries and views used as subqueries are only re-run if the data in one of
the tables was changed. This option is enabled by default.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting can be appended to the database URL: ""jdbc:h2:test;OPTIMIZE_REUSE_RESULTS=0""
","
SET OPTIMIZE_REUSE_RESULTS 0
"

"Commands (Other)","SET PASSWORD","
SET PASSWORD string
","
Changes the password of the current user. The password must be in single quotes.
It is case sensitive and can contain spaces.

This command commits an open transaction.
","
SET PASSWORD 'abcstzri!.5'
"

"Commands (Other)","SET QUERY_TIMEOUT","
SET QUERY_TIMEOUT int
","
Set the query timeout of the current session to the given value. The timeout is
in milliseconds. All kinds of statements will throw an exception if they take
longer than the given value. The default timeout is 0, meaning no timeout.

This command does not commit a transaction, and rollback does not affect it.
","
SET QUERY_TIMEOUT 10000
"

"Commands (Other)","SET REFERENTIAL_INTEGRITY","
SET REFERENTIAL_INTEGRITY { TRUE | FALSE }
","
Disabled or enables referential integrity checking for the whole database.
Enabling it does not check existing data. Use ALTER TABLE SET to disable it only
for one table.

This setting is not persistent.
This command commits an open transaction.
Admin rights are required to execute this command.
","
SET REFERENTIAL_INTEGRITY FALSE
"

"Commands (Other)","SET SALT HASH","
SET SALT bytes HASH bytes
","
Sets the password salt and hash for the current user. The password must be in
single quotes. It is case sensitive and can contain spaces.

This command commits an open transaction.
","
SET SALT '00' HASH '1122'
"

"Commands (Other)","SET SCHEMA","
SET SCHEMA schemaName
","
Changes the default schema of the current connection. The default schema is used
in statements where no schema is set explicitly. The default schema for new
connections is PUBLIC.

This command does not commit a transaction, and rollback does not affect it.
This setting can be appended to the database URL: ""jdbc:h2:test;SCHEMA=ABC""
","
SET SCHEMA INFORMATION_SCHEMA
"

"Commands (Other)","SET SCHEMA_SEARCH_PATH","
SET SCHEMA_SEARCH_PATH schemaName [,...]
","
Changes the schema search path of the current connection. The default schema is
used in statements where no schema is set explicitly. The default schema for new
connections is PUBLIC.

This command does not commit a transaction, and rollback does not affect it.
This setting can be appended to the database URL: ""jdbc:h2:test;SCHEMA_SEARCH_PATH=ABC,DEF""
","
SET SCHEMA_SEARCH_PATH INFORMATION_SCHEMA, PUBLIC
"

"Commands (Other)","SET THROTTLE","
SET THROTTLE int
","
Sets the throttle for the current connection. The value is the number of
milliseconds delay after each 50 ms. The default value is 0 (throttling
disabled).

This command does not commit a transaction, and rollback does not affect it.
This setting can be appended to the database URL: ""jdbc:h2:test;THROTTLE=50""
","
SET THROTTLE 200
"

"Commands (Other)","SET TRACE_LEVEL","
SET { TRACE_LEVEL_FILE | TRACE_LEVEL_SYSTEM_OUT } int
","
Sets the trace level for file the file or system out stream. Levels are: 0=off,
1=error, 2=info, 3=debug. The default level is 1 for file and 0 for system out.
To use SLF4J, append "";TRACE_LEVEL_FILE=4"" to the database URL when opening the database.

This setting is not persistent.
Admin rights are required to execute this command.
This command does not commit a transaction, and rollback does not affect it.
This setting can be appended to the database URL: ""jdbc:h2:test;TRACE_LEVEL_SYSTEM_OUT=3""
","
SET TRACE_LEVEL_SYSTEM_OUT 3
"

"Commands (Other)","SET TRACE_MAX_FILE_SIZE","
SET TRACE_MAX_FILE_SIZE int
","
Sets the maximum trace file size. If the file exceeds the limit, the file is
renamed to .old and a new file is created. If another .old file exists, it is
deleted. The default max size is 16 MB.

This setting is persistent.
Admin rights are required to execute this command.
This command commits an open transaction.
This setting can be appended to the database URL: ""jdbc:h2:test;TRACE_MAX_FILE_SIZE=3""
","
SET TRACE_MAX_FILE_SIZE 10
"

"Commands (Other)","SET UNDO_LOG","
SET UNDO_LOG int
","
Enables (1) or disables (0) the per session undo log. The undo log is enabled by
default. When disabled, transactions can not be rolled back. This setting should
only be used for bulk operations that don't need to be atomic.

This command commits an open transaction.
","
SET UNDO_LOG 0
"

"Commands (Other)","SET WRITE_DELAY","
SET WRITE_DELAY int
","
Set the maximum delay between a commit and flushing the log, in milliseconds.
This setting is persistent. The default is 500 ms.

Admin rights are required to execute this command.
This command commits an open transaction.
This setting can be appended to the database URL: ""jdbc:h2:test;WRITE_DELAY=0""
","
SET WRITE_DELAY 2000
"

"Commands (Other)","SHUTDOWN","
SHUTDOWN [ IMMEDIATELY | COMPACT | DEFRAG ]
","
This statement closes all open connections to the database and closes the
database. This command is usually not required, as the database is
closed automatically when the last connection to it is closed.

If no option is used, then the database is closed normally.
All connections are closed, open transactions are rolled back.

SHUTDOWN COMPACT fully compacts the database (re-creating the database may further reduce the database size).
If the database is closed normally (using SHUTDOWN or by closing all connections), then the database is also compacted,
but only for at most the time defined by the database setting ""h2.maxCompactTime"" (see there).

SHUTDOWN IMMEDIATELY closes the database files without any cleanup and without compacting.

SHUTDOWN DEFRAG re-orders the pages when closing the database so that table scans are faster.

Admin rights are required to execute this command.
","
SHUTDOWN COMPACT
"

"Other Grammar","Alias","
name
","
An alias is a name that is only valid in the context of the statement.
","
A
"

"Other Grammar","And Condition","
condition [ { AND condition } [...] ]
","
Value or condition.
","
ID=1 AND NAME='Hi'
"

"Other Grammar","Array","
( [ expression, [ expression [,...] ] ] )
","
An array of values. An empty array is '()'. Trailing commas are ignored.
An array with one element must contain a comma to be parsed as an array.
","
(1, 2)
(1, )
()
"

"Other Grammar","Boolean","
TRUE | FALSE
","
A boolean value.
","
TRUE
"

"Other Grammar","Bytes","
X'hex'
","
A binary value. The hex value is not case sensitive.
","
X'01FF'
"

"Other Grammar","Case","
CASE expression { WHEN expression THEN expression } [...]
[ ELSE expression ] END
","
Returns the first expression where the value is equal to the test expression. If
no else part is specified, return NULL.
","
CASE CNT WHEN 0 THEN 'No' WHEN 1 THEN 'One' ELSE 'Some' END
"

"Other Grammar","Case When","
CASE { WHEN expression THEN expression} [...]
[ ELSE expression ] END
","
Returns the first expression where the condition is true. If no else part is
specified, return NULL.
","
CASE WHEN CNT<10 THEN 'Low' ELSE 'High' END
"

"Other Grammar","Cipher","
{ AES | XTEA }
","
Two algorithms are supported: AES (""AES-128"") and XTEA (using 32 rounds).
XTEA is a bit faster than AES in some environments, but AES is more secure.
","
AES
"

"Other Grammar","Column Definition","
columnName dataType
[ { DEFAULT expression | AS computedColumnExpression } ] [ [ NOT ] NULL ]
[ { AUTO_INCREMENT | IDENTITY } [ ( startInt [, incrementInt ] ) ] ]
[ SELECTIVITY selectivity ] [ COMMENT expression ]
[ PRIMARY KEY [ HASH ] | UNIQUE ] [ CHECK condition ]
","
Default expressions are used if no explicit value was used when adding a row.
The computed column expression is evaluated and assigned whenever the row changes.

Identity and auto-increment columns are columns with a sequence as the
default. The column declared as the identity columns is implicitly the
primary key column of this table (unlike auto-increment columns).
","
CREATE TABLE TEST(ID INT PRIMARY KEY, NAME VARCHAR(255) DEFAULT '');
CREATE TABLE TEST(ID BIGINT IDENTITY);
CREATE TABLE TEST(QUANTITY INT, PRICE DECIMAL, AMOUNT DECIMAL AS QUANTITY*PRICE);
"

"Other Grammar","Comments","
-- anythingUntilEndOfLine | // anythingUntilEndOfLine | /* anythingUntilEndComment */
","
Comments can be used anywhere in a command and are ignored by the database. Line
comments end with a newline. Block comments cannot be nested, but can be
multiple lines long.
","
// This is a comment
"

"Other Grammar","Compare","
<> | <= | >= | = | < | > | !=
","
Comparison operator. The operator != is the same as <>.
","
<>
"

"Other Grammar","Condition","
operand [ conditionRightHandSide ] | NOT condition | EXISTS ( select )
","
Boolean value or condition.
","
ID<>2
"

"Other Grammar","Condition Right Hand Side","
compare { { { ALL | ANY | SOME } ( select ) } | operand }
    | IS [ NOT ] NULL
    | IS [ NOT ] [ DISTINCT FROM ] operand
    | BETWEEN operand AND operand
    | IN ( { select | expression [,...] } )
    | [ NOT ] LIKE operand [ ESCAPE string ]
    | [ NOT ] REGEXP operand
","
The right hand side of a condition.

The conditions ""IS [ NOT ]"" and ""IS [ NOT ] DISTINCT FROM"" are null-safe, meaning
NULL is considered the same as NULL, and the condition never evaluates to NULL.

When comparing with LIKE, the wildcards characters are ""_"" (any one character)
and ""%"" (any characters). The database uses an index when comparing with LIKE
except if the operand starts with a wildcard. To search for the characters ""%"" and
""_"", the characters need to be escaped. The default escape character is "" \ "" (backslash).
To select no escape character, use ""ESCAPE ''"" (empty string).
At most one escape character is allowed.
Each character that follows the escape character in the pattern needs to match exactly.
Patterns that end with an escape character are invalid and the expression returns NULL.

When comparing with REGEXP, regular expression matching is used.
See Java ""Matcher.find"" for details.
","
LIKE 'Jo%'
"

"Other Grammar","Constraint","
[ constraintNameDefinition ] {
    CHECK expression | UNIQUE ( columnName [,...] )
    | referentialConstraint }
    | PRIMARY KEY [ HASH ] ( columnName [,...] )
","
Defines a constraint.
The check condition must evaluate to TRUE, FALSE or NULL.
TRUE and NULL mean the operation is to be permitted,
and FALSE means the operation is to be rejected.
To prevent NULL in a column, use NOT NULL instead of a check constraint.
","
PRIMARY KEY(ID, NAME)
"

"Other Grammar","Constraint Name Definition","
CONSTRAINT [ IF NOT EXISTS ] newConstraintName
","
Defines a constraint name.
","
CONSTRAINT CONST_ID
"

"Other Grammar","Csv Options","
charsetString [, fieldSepString [, fieldDelimString [, escString [, nullString]]]]]
    | optionString
","
Optional parameters for CSVREAD and CSVWRITE.
Instead of setting the options one by one, all options can be
combined into a space separated key-value pairs, as follows:
""STRINGDECODE('charset=UTF-8 escape=\"" fieldDelimiter=\"" fieldSeparator=, ' ||""
""'lineComment=# lineSeparator=\n null= rowSeparator=')"".
The following options are supported:
""charset"", ""escape"", ""fieldDelimiter"", ""fieldSeparator"",
""lineComment"" (""#"" for H2 version 1.2, disabled for H2 version 1.3),
""lineSeparator"", ""null"", ""rowSeparator"" (not set by default).
For a newline or other special character, use STRINGDECODE as in the example above.
A space needs to be escaped with a backslash (""'\ '"").
A backslash needs to be escaped with another backslash (""'\\'"").
","
CALL CSVWRITE('test2.csv', 'SELECT * FROM TEST', 'charset=UTF-8 fieldSeparator=|');
"

"Other Grammar","Data Type","
intType | booleanType | tinyintType | smallintType | bigintType | identityType
    | decimalType | doubleType | realType | dateType | timeType | timestampType
    | binaryType | otherType | varcharType | varcharIgnorecaseType | charType
    | blobType | clobType | uuidType | arrayType
","
A data type definition.
","
INT
"

"Other Grammar","Date","
DATE 'yyyy-MM-dd'
","
A date literal. The limitations are the same as for the Java data type
""java.sql.Date"", but for compatibility with other databases the suggested minimum
and maximum years are 0001 and 9999.
","
DATE '2004-12-31'
"

"Other Grammar","Decimal","
[ + | - ] number [ . number ]
","
Number with fixed precision and scale.
","
-1600.05
"

"Other Grammar","Digit","
0-9
","
A digit.
","
0
"

"Other Grammar","Dollar Quoted String","
$$anythingExceptTwoDollarSigns$$
","
A string starts and ends with two dollar signs. Two dollar signs are not allowed
within the text. A whitespace is required before the first set of dollar signs.
No escaping is required within the text.
","
$$John's car$$
"

"Other Grammar","Double","
[ + | - ] { { number [ . number ] } | { . number } } [ E [ + | - ] expNumber [...] ] ]
","
A floating point number with high precision.
The limitations are the same as for the Java data type Double.
To ensure the floating point representation is used, use CAST.
There are some special values: to represent positive infinity, use ""POWER(0, -1)"";
for negative infinity, use ""(-POWER(0, -1))""; for -0.0, use ""(-CAST(0 AS DOUBLE))"";
for ""NaN"" (not a number), use ""SQRT(-1)"".
","
-1.4e-10
CAST(0 AS DOUBLE)
"

"Other Grammar","Expression","
andCondition [ { OR andCondition } [...] ]
","
Value or condition.
","
ID=1 OR NAME='Hi'
"

"Other Grammar","Factor","
term [ { { * | / | % } term } [...] ]
","
A value or a numeric factor.
","
ID * 10
"

"Other Grammar","Hex","
{ { digit | a-f | A-F } { digit | a-f | A-F } } [...]
","
The hexadecimal representation of a number or of bytes. Two characters are one
byte.
","
cafe
"

"Other Grammar","Hex Number","
[ + | - ] 0x hex
","
A number written in hexadecimal notation.
","
0xff
"

"Other Grammar","Index Column","
columnName [ ASC | DESC ] [ NULLS { FIRST | LAST } ]
","
Indexes this column in ascending or descending order. Usually it is not required
to specify the order; however doing so will speed up large queries that order
the column in the same way.
","
NAME
"

"Other Grammar","Int","
[ + | - ] number
","
The maximum integer number is 2147483647, the minimum is -2147483648.
","
10
"

"Other Grammar","Long","
[ + | - ] number
","
Long numbers are between -9223372036854775808 and 9223372036854775807.
","
100000
"

"Other Grammar","Name","
{ { A-Z|_  } [ { A-Z|_|0-9 } [...] ] } | quotedName
","
Names are not case sensitive. There is no maximum name length.
","
TEST
"

"Other Grammar","Null","
NULL
","
NULL is a value without data type and means 'unknown value'.
","
NULL
"

"Other Grammar","Number","
digit [...]
","
The maximum length of the number depends on the data type used.
","
100
"

"Other Grammar","Operand","
summand [ { || summand } [...] ]
","
A value or a concatenation of values.
","
'Hi' || ' Eva'
"

"Other Grammar","Order","
{ int | expression } [ ASC | DESC ] [ NULLS { FIRST | LAST } ]
","
Sorts the result by the given column number, or by an expression. If the
expression is a single parameter, then the value is interpreted as a column
number. Negative column numbers reverse the sort order.
","
NAME DESC NULLS LAST
"

"Other Grammar","Quoted Name","
""anythingExceptDoubleQuote""
","
Quoted names are case sensitive, and can contain spaces. There is no maximum
name length. Two double quotes can be used to create a single double quote
inside an identifier.
","
""FirstName""
"

"Other Grammar","Referential Constraint","
FOREIGN KEY ( columnName [,...] )
REFERENCES [ refTableName ] [ ( refColumnName [,...] ) ]
[ ON DELETE { CASCADE | RESTRICT | NO ACTION | SET { DEFAULT | NULL } } ]
[ ON UPDATE { CASCADE | SET { DEFAULT | NULL } } ]
","
Defines a referential constraint. If the table name is not specified, then the
same table is referenced. RESTRICT is the default action.
As this database does not support deferred checking,
RESTRICT and NO ACTION will both throw an exception if the constraint is violated.
If the referenced columns are not specified, then the primary key columns are used.
The required indexes are automatically created if required.
Some tables may not be referenced, such as metadata tables.
","
FOREIGN KEY(ID) REFERENCES TEST(ID)
"

"Other Grammar","Script Compression","
COMPRESSION { DEFLATE | LZF | ZIP | GZIP }
","
The compression algorithm to use for script files.
LZF is faster but uses more space.
","
COMPRESSION LZF
"

"Other Grammar","Select Expression","
* | expression [ [ AS ] columnAlias ] | tableAlias.*
","
An expression in a SELECT statement.
","
ID AS VALUE
"

"Other Grammar","String","
'anythingExceptSingleQuote'
","
A string starts and ends with a single quote. Two single quotes can be used to
create a single quote inside a string.
","
'John''s car'
"

"Other Grammar","Summand","
factor [ { { + | - } factor } [...] ]
","
A value or a numeric sum.

Please note the text concatenation operator is ""||"".
","
ID + 20
"

"Other Grammar","Table Expression","
{ [ schemaName. ] tableName | ( select ) } [ [ AS ] newTableAlias ]
[ { { LEFT | RIGHT } [ OUTER ] | [ INNER ] | CROSS | NATURAL }
    JOIN tableExpression [ ON expression ] ]
","
Joins a table. The join expression is not supported for cross and natural joins.
A natural join is an inner join, where the condition is automatically on the
columns with the same name.
","
TEST AS T LEFT JOIN TEST AS T1 ON T.ID = T1.ID
"

"Other Grammar","Term","
value
    | columnName
    | ?[ int ]
    | NEXT VALUE FOR sequenceName
    | function
    | { - | + } term
    | ( expression )
    | select
    | case
    | caseWhen
    | tableAlias.columnName
","
A value. Parameters can be indexed, for example ""?1"" meaning the first parameter.
Each table has a pseudo-column named ""_ROWID_"" that contains the unique row identifier.
","
'Hello'
"

"Other Grammar","Time","
TIME 'hh:mm:ss'
","
A time literal.
","
TIME '23:59:59'
"

"Other Grammar","Timestamp","
TIMESTAMP 'yyyy-MM-dd hh:mm:ss[.nnnnnnnnn]'
","
A timestamp literal. The limitations are the same as for the Java data type
""java.sql.Timestamp"", but for compatibility with other databases the suggested
minimum and maximum years are 0001 and 9999.
","
TIMESTAMP '2005-12-31 23:59:59'
"

"Other Grammar","Value","
string | dollarQuotedString | hexNumber | int | long | decimal | double
    | date | time | timestamp | boolean | bytes | array | null
","
A value of any data type, or null.
","
10
"

"Data Types","INT Type","
INT | INTEGER | MEDIUMINT | INT4 | SIGNED
","
Possible values: -2147483648 to 2147483647.

Mapped to ""java.lang.Integer"".
","
INT
"

"Data Types","BOOLEAN Type","
BOOLEAN | BIT | BOOL
","
Possible values: TRUE and FALSE.

Mapped to ""java.lang.Boolean"".
","
BOOLEAN
"

"Data Types","TINYINT Type","
TINYINT
","
Possible values are: -128 to 127.

Mapped to ""java.lang.Byte"".
","
TINYINT
"

"Data Types","SMALLINT Type","
SMALLINT | INT2 | YEAR
","
Possible values: -32768 to 32767.

Mapped to ""java.lang.Short"".
","
SMALLINT
"

"Data Types","BIGINT Type","
BIGINT | INT8
","
Possible values: -9223372036854775808 to 9223372036854775807.

Mapped to ""java.lang.Long"".
","
BIGINT
"

"Data Types","IDENTITY Type","
IDENTITY
","
Auto-Increment value. Possible values: -9223372036854775808 to
9223372036854775807. Used values are never re-used, even when the transaction is
rolled back.

Mapped to ""java.lang.Long"".
","
IDENTITY
"

"Data Types","DECIMAL Type","
{ DECIMAL | NUMBER | DEC | NUMERIC } ( precisionInt [ , scaleInt ] )
","
Data type with fixed precision and scale. This data type is recommended for
storing currency values.

Mapped to ""java.math.BigDecimal"".
","
DECIMAL(20, 2)
"

"Data Types","DOUBLE Type","
{ DOUBLE [ PRECISION ] | FLOAT | FLOAT4 | FLOAT8 }
","
A floating point number. Should not be used to represent currency values, because
of rounding problems.

Mapped to ""java.lang.Double"".
","
DOUBLE
"

"Data Types","REAL Type","
REAL
","
A single precision floating point number. Should not be used to represent currency
values, because of rounding problems.

Mapped to ""java.lang.Float"".
","
REAL
"

"Data Types","TIME Type","
TIME
","
The time data type. The format is hh:mm:ss.

Mapped to ""java.sql.Time"". When converted to a ""java.sql.Date"", the date is set to ""1970-01-01"".
","
TIME
"

"Data Types","DATE Type","
DATE
","
The date data type. The format is yyyy-MM-dd.

Mapped to ""java.sql.Date"", with the time set to ""00:00:00""
(or to the next possible time if midnight doesn't exist for the given date and timezone due to a daylight saving change).
","
DATE
"

"Data Types","TIMESTAMP Type","
{ TIMESTAMP | DATETIME | SMALLDATETIME }
","
The timestamp data type. The format is yyyy-MM-dd hh:mm:ss[.nnnnnnnnn].

Mapped to ""java.sql.Timestamp"" (""java.util.Date"" is also supported).
","
TIMESTAMP
"

"Data Types","BINARY Type","
{ BINARY | VARBINARY | LONGVARBINARY | RAW | BYTEA } [ ( precisionInt ) ]
","
Represents a byte array. For very long arrays, use BLOB.
The maximum size is 2 GB, but the whole object is kept in
memory when using this data type. The precision is a size constraint;
only the actual data is persisted. For large text data BLOB or CLOB
should be used.

Mapped to byte[].
","
BINARY(1000)
"

"Data Types","OTHER Type","
OTHER
","
This type allows storing serialized Java objects. Internally, a byte array is
used. Serialization and deserialization is done on the client side only.
Deserialization is only done get ""getObject"" is called. Java operations cannot be
executed inside the database engine for security reasons. Use
""PreparedStatement.setObject"" to store values.

Mapped to ""java.lang.Object"" (or any subclass).
","
OTHER
"

"Data Types","VARCHAR Type","
{ VARCHAR | LONGVARCHAR | VARCHAR2 | NVARCHAR
    | NVARCHAR2 | VARCHAR_CASESENSITIVE}  [ ( precisionInt ) ]
","
Unicode String. Use two single quotes ('') to create a quote. The maximum precision
is ""Integer.MAX_VALUE"". The precision is a size constraint; only the actual data is
persisted. The whole text is kept in memory when using this data type. For large text data CLOB
should be used; see there for details.

Mapped to ""java.lang.String"".
","
VARCHAR(255)
"

"Data Types","VARCHAR_IGNORECASE Type","
VARCHAR_IGNORECASE [ ( precisionInt ) ]
","
Same as VARCHAR, but not case sensitive when comparing. Stored in mixed case.
The maximum precision is ""Integer.MAX_VALUE"" characters, but the whole text is kept in
memory when using this data type. For large text data CLOB should be used;
see there for details.

Mapped to ""java.lang.String"".
","
VARCHAR_IGNORECASE
"

"Data Types","CHAR Type","
{ CHAR | CHARACTER | NCHAR } [ ( precisionInt ) ]
","
This type is supported for compatibility with other databases and older
applications. The difference to VARCHAR is that trailing spaces are ignored and
not persisted. Unicode String. Use two single quotes ('') to create a quote.
The maximum precision is ""Integer.MAX_VALUE"". The precision is a size constraint;
only the actual data is persisted. The whole text is kept in memory when using
this data type. For large text data CLOB should be used; see there for details.

Mapped to ""java.lang.String"".
","
CHAR(10)
"

"Data Types","BLOB Type","
{ BLOB | TINYBLOB | MEDIUMBLOB | LONGBLOB | IMAGE | OID } [ ( precisionInt ) ]
","
Like BINARY, but intended for very large values such as files or images. Unlike
when using BINARY, large objects are not kept fully in-memory. Use
""PreparedStatement.setBinaryStream"" to store values. See also CLOB and
Advanced / Large Objects.

Mapped to ""java.sql.Blob"" (""java.io.InputStream"" is also supported).
","
BLOB
"

"Data Types","CLOB Type","
{ CLOB | TINYTEXT | TEXT | MEDIUMTEXT | LONGTEXT | NTEXT | NCLOB } [ ( precisionInt ) ]
","
CLOB is like VARCHAR, but intended for very large values. Unlike when using
VARCHAR, large CLOB objects are not kept fully in-memory; instead, they are streamed.
CLOB should be used for documents and texts with arbitrary size such as XML or
HTML documents, text files, or memo fields of unlimited size. Use
""PreparedStatement.setCharacterStream"" to store values. See also Advanced / Large Objects.

VARCHAR should be used for text with relatively short average size (for example
shorter than 200 characters). Short CLOB values are stored inline, but there is
an overhead compared to VARCHAR.

Mapped to ""java.sql.Clob"" (""java.io.Reader"" is also supported).
","
CLOB
"

"Data Types","UUID Type","
UUID
","
Universally unique identifier. This is a 128 bit value.
To store values, use ""PreparedStatement.setBytes"",
""setString"", or ""setObject(uuid)"" (where ""uuid"" is a ""java.util.UUID"").
""ResultSet.getObject"" will return a ""java.util.UUID"".

For details, see the documentation of ""java.util.UUID"".
","
UUID
"

"Data Types","ARRAY Type","
ARRAY
","
An array of values. Use a value list (1, 2) or ""PreparedStatement.setObject(.., new Object[] {..})"" to store values.

Mapped to ""java.lang.Object[]"" (arrays of any non-primitive type are also supported).
","
ARRAY
"

"Functions (Aggregate)","AVG","
AVG ( [ DISTINCT ] { int | long | decimal | double } )
","
The average (mean) value.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
The returned value is of the same data type as the parameter.
","
AVG(X)
"

"Functions (Aggregate)","BOOL_AND","
BOOL_AND(boolean)
","
Returns true if all expressions are true.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
BOOL_AND(ID>10)
"

"Functions (Aggregate)","BOOL_OR","
BOOL_OR(boolean)
","
Returns true if any expression is true.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
BOOL_OR(NAME LIKE 'W%')
"

"Functions (Aggregate)","COUNT","
COUNT( { * | { [ DISTINCT ] expression } } )
","
The count of all row, or of the non-null values.
This method returns a long.
If no rows are selected, the result is 0.
Aggregates are only allowed in select statements.
","
COUNT(*)
"

"Functions (Aggregate)","GROUP_CONCAT","
GROUP_CONCAT ( [ DISTINCT ] string
[ ORDER BY { expression [ ASC | DESC ] } [,...] ]
[ SEPARATOR expression ] )
","
Concatenates strings with a separator.
The default separator is a ',' (without space).
This method returns a string.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
GROUP_CONCAT(NAME ORDER BY ID SEPARATOR ', ')
"

"Functions (Aggregate)","MAX","
MAX(value)
","
The highest value.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
The returned value is of the same data type as the parameter.
","
MAX(NAME)
"

"Functions (Aggregate)","MIN","
MIN(value)
","
The lowest value.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
The returned value is of the same data type as the parameter.
","
MIN(NAME)
"

"Functions (Aggregate)","SUM","
SUM( [ DISTINCT ] { int | long | decimal | double } )
","
The sum of all values.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
The returned value is of the same data type as the parameter.
","
SUM(X)
"

"Functions (Aggregate)","SELECTIVITY","
SELECTIVITY(value)
","
Estimates the selectivity (0-100) of a value.
The value is defined as (100 * distinctCount / rowCount).
The selectivity of 0 rows is 0 (unknown).
Up to 10000 values are kept in memory.
Aggregates are only allowed in select statements.
","
SELECT SELECTIVITY(FIRSTNAME), SELECTIVITY(NAME) FROM TEST WHERE ROWNUM()<20000
"

"Functions (Aggregate)","STDDEV_POP","
STDDEV_POP( [ DISTINCT ] double )
","
The population standard deviation.
This method returns a double.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
STDDEV_POP(X)
"

"Functions (Aggregate)","STDDEV_SAMP","
STDDEV_SAMP( [ DISTINCT ] double )
","
The sample standard deviation.
This method returns a double.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
STDDEV(X)
"

"Functions (Aggregate)","VAR_POP","
VAR_POP( [ DISTINCT ] double )
","
The population variance (square of the population standard deviation).
This method returns a double.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
VAR_POP(X)
"

"Functions (Aggregate)","VAR_SAMP","
VAR_SAMP( [ DISTINCT ] double )
","
The sample variance (square of the sample standard deviation).
This method returns a double.
If no rows are selected, the result is NULL.
Aggregates are only allowed in select statements.
","
VAR_SAMP(X)
"

"Functions (Numeric)","ABS","
ABS ( { int | long | decimal | double } )
","
See also Java ""Math.abs"".
Please note that ""Math.abs(Integer.MIN_VALUE) == Integer.MIN_VALUE"" and ""Math.abs(Long.MIN_VALUE) == Long.MIN_VALUE"".
The returned value is of the same data type as the parameter.
","
ABS(ID)
"

"Functions (Numeric)","ACOS","
ACOS(double)
","
Calculate the arc cosine.
See also Java ""Math.acos"".
This method returns a double.
","
ACOS(D)
"

"Functions (Numeric)","ASIN","
ASIN(double)
","
Calculate the arc sine.
See also Java ""Math.asin"".
This method returns a double.
","
ASIN(D)
"

"Functions (Numeric)","ATAN","
ATAN(double)
","
Calculate the arc tangent.
See also Java ""Math.atan"".
This method returns a double.
","
ATAN(D)
"

"Functions (Numeric)","COS","
COS(double)
","
Calculate the trigonometric cosine.
See also Java ""Math.cos"".
This method returns a double.
","
COS(ANGLE)
"

"Functions (Numeric)","COSH","
COSH(double)
","
Calculate the hyperbolic cosine.
See also Java ""Math.cosh"".
This method returns a double.
","
COSH(X)
"

"Functions (Numeric)","COT","
COT(double)
","
Calculate the trigonometric cotangent (""1/TAN(ANGLE)"").
See also Java ""Math.*"" functions.
This method returns a double.
","
COT(ANGLE)
"

"Functions (Numeric)","SIN","
SIN(double)
","
Calculate the trigonometric sine.
See also Java ""Math.sin"".
This method returns a double.
","
SIN(ANGLE)
"

"Functions (Numeric)","SINH","
SINH(double)
","
Calculate the hyperbolic sine.
See also Java ""Math.sinh"".
This method returns a double.
","
SINH(ANGLE)
"

"Functions (Numeric)","TAN","
TAN(double)
","
Calculate the trigonometric tangent.
See also Java ""Math.tan"".
This method returns a double.
","
TAN(ANGLE)
"

"Functions (Numeric)","TANH","
TANH(double)
","
Calculate the hyperbolic tangent.
See also Java ""Math.tanh"".
This method returns a double.
","
TANH(X)
"

"Functions (Numeric)","ATAN2","
ATAN2(double, double)
","
Calculate the angle when converting the rectangular coordinates to polar coordinates.
See also Java ""Math.atan2"".
This method returns a double.
","
ATAN2(X, Y)
"

"Functions (Numeric)","BITAND","
BITAND(long, long)
","
The bitwise AND operation.
This method returns a long.
See also Java operator &.
","
BITAND(A, B)
"

"Functions (Numeric)","BITOR","
BITOR(long, long)
","
The bitwise OR operation.
This method returns a long.
See also Java operator |.
","
BITOR(A, B)
"

"Functions (Numeric)","BITXOR","
BITXOR(long, long)
","
The bitwise XOR operation.
This method returns a long.
See also Java operator ^.
","
BITXOR(A, B)
"

"Functions (Numeric)","MOD","
MOD(long, long)
","
The modulo operation.
This method returns a long.
See also Java operator %.
","
MOD(A, B)
"

"Functions (Numeric)","CEILING","
CEILING(double)
","
See also Java ""Math.ceil"".
This method returns a double.
","
LOG(A)
"

"Functions (Numeric)","DEGREES","
DEGREES(double)
","
See also Java ""Math.toDegrees"".
This method returns a double.
","
DEGREES(A)
"

"Functions (Numeric)","EXP","
EXP(double)
","
See also Java ""Math.exp"".
This method returns a double.
","
EXP(A)
"

"Functions (Numeric)","FLOOR","
FLOOR(double)
","
See also Java ""Math.floor"".
This method returns a double.
","
FLOOR(A)
"

"Functions (Numeric)","LOG","
LOG(double)
","
See also Java ""Math.log"".
This method returns a double.
","
LOG(A)
"

"Functions (Numeric)","LOG10","
LOG10(double)
","
See also Java ""Math.log10"" (in Java 5).
This method returns a double.
","
LOG10(A)
"

"Functions (Numeric)","RADIANS","
RADIANS(double)
","
See also Java ""Math.toRadians"".
This method returns a double.
","
RADIANS(A)
"

"Functions (Numeric)","SQRT","
SQRT(double)
","
See also Java ""Math.sqrt"".
This method returns a double.
","
SQRT(A)
"

"Functions (Numeric)","PI","
PI()
","
See also Java ""Math.PI"".
This method returns a double.
","
PI()
"

"Functions (Numeric)","POWER","
POWER(double, double)
","
See also Java ""Math.pow"".
This method returns a double.
","
POWER(A, B)
"

"Functions (Numeric)","RAND","
RAND( [ int ] )
","
Calling the function without parameter returns the next a pseudo random number.
Calling it with an parameter seeds the session's random number generator.
This method returns a double between 0 (including) and 1 (excluding).
","
RAND()
"

"Functions (Numeric)","RANDOM_UUID","
RANDOM_UUID()
","
Returns a new UUID with 122 pseudo random bits.
","
RANDOM_UUID()
"

"Functions (Numeric)","ROUND","
ROUND(double, digitsInt)
","
Rounds to a number of digits.
This method returns a double.
","
ROUND(VALUE, 2)
"

"Functions (Numeric)","ROUNDMAGIC","
ROUNDMAGIC(double)
","
This function rounds numbers in a good way, but it is slow.
It has a special handling for numbers around 0.
Only numbers smaller or equal +/-1000000000000 are supported.
The value is converted to a String internally, and then the last last 4 characters are checked.
'000x' becomes '0000' and '999x' becomes '999999', which is rounded automatically.
This method returns a double.
","
ROUNDMAGIC(VALUE/3*3)
"

"Functions (Numeric)","SECURE_RAND","
SECURE_RAND(int)
","
Generates a number of cryptographically secure random numbers.
This method returns bytes.
","
CALL SECURE_RAND(16)
"

"Functions (Numeric)","SIGN","
SIGN ( { int | long | decimal | double } )
","
Returns -1 if the value is smaller 0, 0 if zero, and otherwise 1.
","
SIGN(VALUE)
"

"Functions (Numeric)","ENCRYPT","
ENCRYPT(algorithmString, keyBytes, dataBytes)
","
Encrypts data using a key.
Supported algorithms are XTEA and AES.
The block size is 16 bytes.
This method returns bytes.
","
CALL ENCRYPT('AES', '00', STRINGTOUTF8('Test'))
"

"Functions (Numeric)","DECRYPT","
DECRYPT(algorithmString, keyBytes, dataBytes)
","
Decrypts data using a key.
Supported algorithms are XTEA and AES.
The block size is 16 bytes.
This method returns bytes.
","
CALL TRIM(CHAR(0) FROM UTF8TOSTRING(
    DECRYPT('AES', '00', '3fabb4de8f1ee2e97d7793bab2db1116')))
"

"Functions (Numeric)","HASH","
HASH(algorithmString, dataBytes, iterationInt)
","
Calculate the hash value using an algorithm, and repeat this process for a number of iterations.
Currently, the only algorithm supported is SHA256.
This method returns bytes.
","
CALL HASH('SHA256', STRINGTOUTF8('Password'), 1000)
"

"Functions (Numeric)","TRUNCATE","
TRUNCATE(double, digitsInt)
","
Truncates to a number of digits (to the next value closer to 0).
This method returns a double.
","
TRUNCATE(VALUE, 2)
"

"Functions (Numeric)","COMPRESS","
COMPRESS(dataBytes [, algorithmString])
","
Compresses the data using the specified compression algorithm.
Supported algorithms are: LZF (faster but lower compression; default), and DEFLATE (higher compression).
Compression does not always reduce size. Very small objects and objects with little redundancy may get larger.
This method returns bytes.
","
COMPRESS(STRINGTOUTF8('Test'))
"

"Functions (Numeric)","EXPAND","
EXPAND(bytes)
","
Expands data that was compressed using the COMPRESS function.
This method returns bytes.
","
UTF8TOSTRING(EXPAND(COMPRESS(STRINGTOUTF8('Test'))))
"

"Functions (Numeric)","ZERO","
ZERO()
","
Returns the value 0. This function can be used even if numeric literals are disabled.
","
ZERO()
"

"Functions (String)","ASCII","
ASCII(string)
","
Returns the ASCII value of the first character in the string.
This method returns an int.
","
ASCII('Hi')
"
"Functions (String)","BIT_LENGTH","
BIT_LENGTH(string)
","
Returns the number of bits in a string.
This method returns a long.
For BLOB, CLOB, BYTES and JAVA_OBJECT, the precision is used. Each character needs 16 bits.
","
BIT_LENGTH(NAME)
"

"Functions (String)","LENGTH","
{ LENGTH | CHAR_LENGTH | CHARACTER_LENGTH } ( string )
","
Returns the number of characters in a string.
This method returns a long.
For BLOB, CLOB, BYTES and JAVA_OBJECT, the precision is used.
","
LENGTH(NAME)
"

"Functions (String)","OCTET_LENGTH","
OCTET_LENGTH(string)
","
Returns the number of bytes in a string.
This method returns a long.
For BLOB, CLOB, BYTES and JAVA_OBJECT, the precision is used.
Each character needs 2 bytes.
","
OCTET_LENGTH(NAME)
"

"Functions (String)","CHAR","
{ CHAR | CHR } ( int )
","
Returns the character that represents the ASCII value.
This method returns a string.
","
CHAR(65)
"

"Functions (String)","CONCAT","
CONCAT(string, string [,...])
","
Combines strings.
This method returns a string.
","
CONCAT(NAME, '!')
"

"Functions (String)","DIFFERENCE","
DIFFERENCE(string, string)
","
Returns the difference between the sounds of two strings.
This method returns an int.
","
DIFFERENCE(T1.NAME, T2.NAME)
"

"Functions (String)","HEXTORAW","
HEXTORAW(string)
","
Converts a hex representation of a string to a string.
4 hex characters per string character are used.
","
HEXTORAW(DATA)
"

"Functions (String)","RAWTOHEX","
RAWTOHEX(string)
","
Converts a string to the hex representation.
4 hex characters per string character are used.
This method returns a string.
","
RAWTOHEX(DATA)
"

"Functions (String)","INSTR","
INSTR(string, searchString, [, startInt])
","
Returns the location of a search string in a string.
If a start position is used, the characters before it are ignored.
If position is negative, the rightmost location is returned.
0 is returned if the search string is not found.
","
INSTR(EMAIL,'@')
"

"Functions (String)","INSERT Function","
INSERT(originalString, startInt, lengthInt, addString)
","
Inserts a additional string into the original string at a specified start position.
The length specifies the number of characters that are removed at the start position in the original string.
This method returns a string.
","
INSERT(NAME, 1, 1, ' ')
"

"Functions (String)","LOWER","
{ LOWER | LCASE } ( string )
","
Converts a string to lowercase.
","
LOWER(NAME)
"

"Functions (String)","UPPER","
{ UPPER | UCASE } ( string )
","
Converts a string to uppercase.
","
UPPER(NAME)
"

"Functions (String)","LEFT","
LEFT(string, int)
","
Returns the leftmost number of characters.
","
LEFT(NAME, 3)
"

"Functions (String)","RIGHT","
RIGHT(string, int)
","
Returns the rightmost number of characters.
","
RIGHT(NAME, 3)
"

"Functions (String)","LOCATE","
LOCATE(searchString, string [, startInt])
","
Returns the location of a search string in a string.
If a start position is used, the characters before it are ignored.
If position is negative, the rightmost location is returned.
0 is returned if the search string is not found.
","
LOCATE('.', NAME)
"

"Functions (String)","POSITION","
POSITION(searchString, string)
","
Returns the location of a search string in a string. See also LOCATE.
","
POSITION('.', NAME)
"

"Functions (String)","LPAD","
LPAD(string, int[, paddingString])
","
Left pad the string to the specified length.
If the length is shorter than the string, it will be truncated at the end.
If the padding string is not set, spaces will be used.
","
LPAD(AMOUNT, 10, '*')
"

"Functions (String)","RPAD","
RPAD(string, int[, paddingString])
","
Right pad the string to the specified length.
If the length is shorter than the string, it will be truncated.
If the padding string is not set, spaces will be used.
","
RPAD(TEXT, 10, '-')
"

"Functions (String)","LTRIM","
LTRIM(string)
","
Removes all leading spaces from a string.
","
LTRIM(NAME)
"

"Functions (String)","RTRIM","
RTRIM(string)
","
Removes all trailing spaces from a string.
","
RTRIM(NAME)
"

"Functions (String)","TRIM","
TRIM ( [ { LEADING | TRAILING | BOTH } [ string ] FROM ] string )
","
Removes all leading spaces, trailing spaces, or spaces at both ends, from a string.
Other characters can be removed as well.
","
TRIM(BOTH '_' FROM NAME)
"

"Functions (String)","REGEXP_REPLACE","
REGEXP_REPLACE(inputString, regexString, replacementString)
","
Replaces each substring that matches a regular expression.
For details, see the Java ""String.replaceAll()"" method.
If any parameter is null, the result is null.
","
REGEXP_REPLACE('Hello    World', ' +', ' ')
"

"Functions (String)","REPEAT","
REPEAT(string, int)
","
Returns a string repeated some number of times.
","
REPEAT(NAME || ' ', 10)
"

"Functions (String)","REPLACE","
REPLACE(string, searchString [, replacementString])
","
Replaces all occurrences of a search string in a text with another string.
If no replacement is specified, the search string is removed from the original string.
If any parameter is null, the result is null.
","
REPLACE(NAME, ' ')
"

"Functions (String)","SOUNDEX","
SOUNDEX(string)
","
Returns a four character code representing the sound of a string.
See also http://www.archives.gov/genealogy/census/soundex.html .
This method returns a string.
","
SOUNDEX(NAME)
"

"Functions (String)","SPACE","
SPACE(int)
","
Returns a string consisting of a number of spaces.
","
SPACE(80)
"

"Functions (String)","STRINGDECODE","
STRINGDECODE(string)
","
Converts a encoded string using the Java string literal encoding format.
Special characters are \b, \t, \n, \f, \r, \"", \\, \<octal>, \u<unicode>.
This method returns a string.
","
CALL STRINGENCODE(STRINGDECODE('Lines 1\nLine 2'))
"

"Functions (String)","STRINGENCODE","
STRINGENCODE(string)
","
Encodes special characters in a string using the Java string literal encoding format.
Special characters are \b, \t, \n, \f, \r, \"", \\, \<octal>, \u<unicode>.
This method returns a string.
","
CALL STRINGENCODE(STRINGDECODE('Lines 1\nLine 2'))
"

"Functions (String)","STRINGTOUTF8","
STRINGTOUTF8(string)
","
Encodes a string to a byte array using the UTF8 encoding format.
This method returns bytes.
","
CALL UTF8TOSTRING(STRINGTOUTF8('This is a test'))
"

"Functions (String)","SUBSTRING","
{ SUBSTRING | SUBSTR } ( string, startInt [, lengthInt ] )
","
Returns a substring of a string starting at a position.
The length is optional.
Also supported is: ""SUBSTRING(string FROM start [FOR length])"".
","
SUBSTR(NAME, 1)
"

"Functions (String)","UTF8TOSTRING","
UTF8TOSTRING(bytes)
","
Decodes a byte array in the UTF8 format to a string.
","
CALL UTF8TOSTRING(STRINGTOUTF8('This is a test'))
"

"Functions (String)","XMLATTR","
XMLATTR(nameString, valueString)
","
Creates an XML attribute element of the form ""name=value"".
The value is encoded as XML text.
This method returns a string.
","
CALL XMLNODE('a', XMLATTR('href', 'http://h2database.com'))
"

"Functions (String)","XMLNODE","
XMLNODE(elementString [, attributesString [, contentString]])
","
Create an XML node element.
This method returns a string.
","
CALL XMLNODE('a', XMLATTR('href', 'http://h2database.com'), 'H2')
"

"Functions (String)","XMLCOMMENT","
XMLCOMMENT(commentString)
","
Creates an XML comment.
Two dashes (""--"") are converted to ""- -"".
This method returns a string.
","
CALL XMLCOMMENT('Test')
"

"Functions (String)","XMLCDATA","
XMLCDATA(valueString)
","
Creates an XML CDATA element.
If the value contains ""]]>"", an XML text element is created instead.
This method returns a string.
","
CALL XMLCDATA('data')
"

"Functions (String)","XMLSTARTDOC","
XMLSTARTDOC()
","
The string ""<?xml version='1.0'?>"" is returned.
","
CALL XMLSTARTDOC()
"

"Functions (String)","XMLTEXT","
XMLTEXT(valueString)
","
Creates an XML text element.
This method returns a string.
","
CALL XMLTEXT('test')
"

"Functions (Time and Date)","CURRENT_DATE","
{ CURRENT_DATE [ () ] | CURDATE() | SYSDATE | TODAY }
","
Returns the current date.
","
CURRENT_DATE()
"

"Functions (Time and Date)","CURRENT_TIME","
{ CURRENT_TIME [ () ] | CURTIME() }
","
Returns the current time.
","
CURRENT_TIME()
"

"Functions (Time and Date)","CURRENT_TIMESTAMP","
{ CURRENT_TIMESTAMP [ ( [ int ] ) ] | NOW( [ int ] ) }
","
Returns the current timestamp.
The precision parameter for nanoseconds precision is optional.
","
CURRENT_TIMESTAMP()
"

"Functions (Time and Date)","DATEADD","
DATEADD(unitString, addInt, timestamp)
","
Adds units to a timestamp. The string indicates the unit.
Use negative values to subtract units.
The same units as in the EXTRACT function are supported.
This method returns a timestamp.
","
DATEADD('MONTH', 1, DATE '2001-01-31')
"

"Functions (Time and Date)","DATEDIFF","
{ DATEDIFF | TIMESTAMPDIFF } (unitString, aTimestamp, bTimestamp)
","
Returns the the number of crossed unit boundaries between two timestamps.
This method returns a long.
The string indicates the unit.
The same units as in the EXTRACT function are supported.
TIMESTAMPDIFF is supported for MySQL compatibility.
","
DATEDIFF('YEAR', T1.CREATED, T2.CREATED)
"

"Functions (Time and Date)","DAYNAME","
DAYNAME(date)
","
Returns the name of the day (in English).
","
DAYNAME(CREATED)
"

"Functions (Time and Date)","DAY_OF_MONTH","
DAY_OF_MONTH(date)
","
Returns the day of the month (1-31).
","
DAY_OF_MONTH(CREATED)
"

"Functions (Time and Date)","DAY_OF_WEEK","
DAY_OF_WEEK(date)
","
Returns the day of the week (1 means Sunday).
","
DAY_OF_WEEK(CREATED)
"

"Functions (Time and Date)","DAY_OF_YEAR","
DAY_OF_YEAR(date)
","
Returns the day of the year (1-366).
","
DAY_OF_YEAR(CREATED)
"

"Functions (Time and Date)","EXTRACT","
EXTRACT ( { YEAR | YY | MONTH | MM | DAY | DD | DAY_OF_YEAR
    | DOY | HOUR | HH | MINUTE | MI | SECOND | SS | MILLISECOND | MS }
    FROM timestamp )
","
Returns a specific value from a timestamps.
This method returns an int.
","
EXTRACT(SECOND FROM CURRENT_TIMESTAMP)
"

"Functions (Time and Date)","FORMATDATETIME","
FORMATDATETIME ( timestamp, formatString
[ , localeString [ , timeZoneString ] ] )
","
Formats a date, time or timestamp as a string.
The most important format characters are:
y year, M month, d day, H hour, m minute, s second.
For details of the format, see ""java.text.SimpleDateFormat"".
This method returns a string.
","
CALL FORMATDATETIME(TIMESTAMP '2001-02-03 04:05:06',
    'EEE, d MMM yyyy HH:mm:ss z', 'en', 'GMT')
"

"Functions (Time and Date)","HOUR","
HOUR(timestamp)
","
Returns the hour (0-23) from a timestamp.
","
HOUR(CREATED)
"

"Functions (Time and Date)","MINUTE","
MINUTE(timestamp)
","
Returns the minute (0-59) from a timestamp.
","
MINUTE(CREATED)
"

"Functions (Time and Date)","MONTH","
MONTH(timestamp)
","
Returns the month (1-12) from a timestamp.
","
MONTH(CREATED)
"

"Functions (Time and Date)","MONTHNAME","
MONTHNAME(date)
","
Returns the name of the month (in English).
","
MONTHNAME(CREATED)
"

"Functions (Time and Date)","PARSEDATETIME","
PARSEDATETIME(string, formatString
[, localeString [, timeZoneString]])
","
Parses a string and returns a timestamp.
The most important format characters are:
y year, M month, d day, H hour, m minute, s second.
For details of the format, see ""java.text.SimpleDateFormat"".
","
CALL PARSEDATETIME('Sat, 3 Feb 2001 03:05:06 GMT',
    'EEE, d MMM yyyy HH:mm:ss z', 'en', 'GMT')
"

"Functions (Time and Date)","QUARTER","
QUARTER(timestamp)
","
Returns the quarter (1-4) from a timestamp.
","
QUARTER(CREATED)
"

"Functions (Time and Date)","SECOND","
SECOND(timestamp)
","
Returns the second (0-59) from a timestamp.
","
SECOND(CREATED)
"

"Functions (Time and Date)","WEEK","
WEEK(timestamp)
","
Returns the week (1-53) from a timestamp.
This method uses the current system locale.
","
WEEK(CREATED)
"

"Functions (Time and Date)","YEAR","
YEAR(timestamp)
","
Returns the year from a timestamp.
","
YEAR(CREATED)
"

"Functions (System)","ARRAY_GET","
ARRAY_GET(arrayExpression, indexExpression)
","
Returns one element of an array.
This method returns a string.
","
CALL ARRAY_GET(('Hello', 'World'), 2)
"

"Functions (System)","ARRAY_LENGTH","
ARRAY_GET(arrayExpression)
","
Returns the length of an array.
","
CALL ARRAY_LENGTH(('Hello', 'World'))
"

"Functions (System)","AUTOCOMMIT","
AUTOCOMMIT()
","
Returns true if auto commit is switched on for this session.
","
AUTOCOMMIT()
"

"Functions (System)","CANCEL_SESSION","
CANCEL_SESSION(sessionInt)
","
Cancels the currently executing statement of another session.
The method only works if the multithreaded kernel is enabled (see SET MULTI_THREADED).
Returns true if the statement was canceled, false if the session is closed or no statement is currently executing.

Admin rights are required to execute this command.
","
CANCEL_SESSION(3)
"

"Functions (System)","CASEWHEN Function","
CASEWHEN(boolean, aValue, bValue)
","
Returns 'a' if the boolean expression is true, otherwise 'b'.
Returns the same data type as the parameter.
","
CASEWHEN(ID=1, 'A', 'B')
"

"Functions (System)","CAST","
CAST(value AS dataType)
","
Converts a value to another data type. The following conversion rules are used:
When converting a number to a boolean, 0 is false and every other value is true.
When converting a boolean to a number, false is 0 and true is 1.
When converting a number to a number of another type, the value is checked for overflow.
When converting a number to binary, the number of bytes matches the precision.
When converting a string to binary, it is hex encoded (every byte two characters);
a hex string can be converted to a number by first converting it to binary.
If a direct conversion is not possible, the value is first converted to a string.
","
CAST(NAME AS INT);
CAST(65535 AS BINARY);
CAST(CAST('FFFF' AS BINARY) AS INT);
"

"Functions (System)","COALESCE","
COALESCE(aValue, bValue [,...])
","
Returns the first value that is not null.
","
COALESCE(A, B, C)
"

"Functions (System)","CONVERT","
CONVERT(value, dataType)
","
Converts a value to another data type.
","
CONVERT(NAME, INT)
"

"Functions (System)","CURRVAL","
CURRVAL( [ schemaName, ] sequenceString )
","
Returns the current (last) value of the sequence, independent of the session.
If the sequence was just created, the method returns (start - interval).
If the schema name is not set, the current schema is used.
If the schema name is not set, the sequence name is converted to uppercase (for compatibility).
This method returns a long.
","
CURRVAL('TEST_SEQ')
"

"Functions (System)","CSVREAD","
CSVREAD(fileNameString [, columnsString [, csvOptions ] ] )
","
Returns the result set of reading the CSV (comma separated values) file.
For each parameter, NULL means the default value should be used.

If the column names are specified (a list of column names separated with the
fieldSeparator), those are used, otherwise (or if they are set to NULL) the first line of
the file is interpreted as the column names.
In that case, column names that contain no special characters (only letters, '_',
and digits; similar to the rule for Java identifiers) are considered case insensitive.
Other column names are case sensitive, that means you need to use quoted identifiers
(see below).

The default charset is the default value for this system, and the default field separator
is a comma. Missing unquoted values as well as data that matches nullString is
parsed as NULL. All columns of type VARCHAR.

The BOM (the byte-order-mark) character 0xfeff at the beginning of the file is ignored.

This function can be used like a table: ""SELECT * FROM CSVREAD(...)"".

Instead of a file, an URL may be used, for example
""jar:file:///c:/temp/example.zip!/org/example/nested.csv"".
To read a stream from the classpath, use the prefix ""classpath:"".

Admin rights are required to execute this command.
","
CALL CSVREAD('test.csv');
-- Read a file containing the columns ID, NAME with
-- UTF-8 encoding and the pipe (|) as field separator
CALL CSVREAD('test2.csv', 'ID|NAME', 'UTF-8', '|');
-- Read a semicolon-separated file
SELECT * FROM CSVREAD('data/test.csv', NULL, NULL, ';');
SELECT ""Last Name"" FROM CSVREAD('address.csv');
SELECT ""Last Name"" FROM CSVREAD('classpath:/org/acme/data/address.csv');
"

"Functions (System)","CSVWRITE","
CSVWRITE ( fileNameString, queryString [, csvOptions [, lineSepString] ] )
","
Writes a CSV (comma separated values). The file is overwritten if it exists.
If only a file name is specified, it will be written to the current working directory.
For each parameter, NULL means the default value should be used.
The default charset is the default value for this system, and the default field separator is a comma.

The values are converted to text using the default string representation;
if another conversion is required you need to change the select statement accordingly.
The parameter nullString is used when writing NULL (by default nothing is written
when NULL appears). The default line separator is the default value for this
system (system property ""line.separator"").

The returned value is the number or rows written.
Admin rights are required to execute this command.
","
CALL CSVWRITE('test.csv', 'SELECT * FROM TEST');
-- Write a file with UTF-8 encoding and the pipe (|) as field separator
CALL CSVWRITE('test2.csv', 'SELECT * FROM TEST', 'UTF-8', '|');
"

"Functions (System)","DATABASE","
DATABASE()
","
Returns the name of the database.
","
CALL DATABASE();
"

"Functions (System)","DATABASE_PATH","
DATABASE_PATH()
","
Returns the directory of the database files and the database name, if it is file
based. Returns NULL otherwise.
","
CALL DATABASE_PATH();
"

"Functions (System)","FILE_READ","
FILE_READ(fileNameString [,encodingString])
","
Returns the contents of a file. If only one parameter is supplied, the data are
returned as a BLOB. If two parameters are used, the data is returned as a CLOB
(text). The second parameter is the character set to use, NULL meaning the
default character set for this system.

File names and URLs are supported.
To read a stream from the classpath, use the prefix ""classpath:"".

Admin rights are required to execute this command.
","
SELECT LENGTH(FILE_READ('~/.h2.server.properties')) LEN;
SELECT FILE_READ('http://localhost:8182/stylesheet.css', NULL) CSS;
"

"Functions (System)","GREATEST","
GREATEST(aValue, bValue [,...])
","
Returns the largest value that is not NULL, or NULL if all values are NULL.
","
CALL GREATEST(1, 2, 3);
"

"Functions (System)","IDENTITY","
IDENTITY()
","
Returns the last inserted identity value for this session.
This value changes whenever a new sequence number was generated,
even within a trigger or Java function. See also SCOPE_IDENTITY.
This method returns a long.
","
CALL IDENTITY();
"

"Functions (System)","IFNULL","
IFNULL(aValue, bValue)
","
Returns the value of 'a' if it is not null, otherwise 'b'.
","
CALL IFNULL(NULL, '');
"

"Functions (System)","LEAST","
LEAST(aValue, bValue [,...])
","
Returns the smallest value that is not NULL, or NULL if all values are NULL.
","
CALL LEAST(1, 2, 3);
"

"Functions (System)","LOCK_MODE","
LOCK_MODE()
","
Returns the current lock mode. See SET LOCK_MODE.
This method returns an int.
","
CALL LOCK_MODE();
"

"Functions (System)","LOCK_TIMEOUT","
LOCK_TIMEOUT()
","
Returns the lock timeout of the current session (in milliseconds).
","
LOCK_TIMEOUT()
"

"Functions (System)","LINK_SCHEMA","
LINK_SCHEMA(targetSchemaString, driverString, urlString,
userString, passwordString, sourceSchemaString)
","
Creates table links for all tables in a schema.
If tables with the same name already exist, they are dropped first.
The target schema is created automatically if it does not yet exist.
The driver name may be empty if the driver is already loaded.
The list of tables linked is returned in the form of a result set.
Admin rights are required to execute this command.
","
CALL LINK_SCHEMA('TEST2', '', 'jdbc:h2:test2', 'sa', 'sa', 'PUBLIC');
"

"Functions (System)","MEMORY_FREE","
MEMORY_FREE()
","
Returns the free memory in KB (where 1024 bytes is a KB).
This method returns an int.
The garbage is run before returning the value.
Admin rights are required to execute this command.
","
MEMORY_FREE()
"

"Functions (System)","MEMORY_USED","
MEMORY_USED()
","
Returns the used memory in KB (where 1024 bytes is a KB).
This method returns an int.
The garbage is run before returning the value.
Admin rights are required to execute this command.
","
MEMORY_USED()
"

"Functions (System)","NEXTVAL","
NEXTVAL ( [ schemaName, ] sequenceString )
","
Returns the next value of the sequence.
Used values are never re-used, even when the transaction is rolled back.
If the schema name is not set, the current schema is used, and the sequence name is converted to uppercase (for compatibility).
This method returns a long.
","
NEXTVAL('TEST_SEQ')
"

"Functions (System)","NULLIF","
NULLIF(aValue, bValue)
","
Returns NULL if 'a' is equals to 'b', otherwise 'a'.
","
NULLIF(A, B)
"

"Functions (System)","READONLY","
READONLY()
","
Returns true if the database is read-only.
","
READONLY()
"

"Functions (System)","ROWNUM","
ROWNUM()
","
Returns the number of the current row.
This method returns an int.
This function is supported for SELECT statements, as well as for DELETE and UPDATE.
The first row has the row number 1, and is calculated before ordering and grouping the result set,
but after evaluating index conditions (even when the  index conditions are specified in an outer query).
To get the row number after ordering and grouping, use a subquery.
","
SELECT ROWNUM(), * FROM TEST;
SELECT ROWNUM(), * FROM (SELECT * FROM TEST ORDER BY NAME);
SELECT ID FROM (SELECT T.*, ROWNUM AS R FROM TEST T) WHERE R BETWEEN 2 AND 3;
"

"Functions (System)","SCHEMA","
SCHEMA()
","
Returns the name of the default  schema for this session.
","
CALL SCHEMA()
"

"Functions (System)","SCOPE_IDENTITY","
SCOPE_IDENTITY()
","
Returns the last inserted identity value for this session for the current scope.
Changes within triggers and Java functions are ignored. See also IDENTITY().
This method returns a long.
","
CALL SCOPE_IDENTITY();
"

"Functions (System)","SESSION_ID","
SESSION_ID()
","
Returns the unique session id number for the current database connection.
This id stays the same while the connection is open.
This method returns an int.
The database engine may re-use a session id after the connection is closed.
","
CALL SESSION_ID()
"

"Functions (System)","SET","
SET(@variableName, value)
","
Updates a variable with the given value.
The new value is returned.
When used in a query, the value is updated in the order the rows are read.
This can be used to implement running totals / cumulative sums.
","
SELECT X, SET(@I, IFNULL(@I, 0)+X) RUNNING_TOTAL FROM SYSTEM_RANGE(1, 10)
"

"Functions (System)","TABLE","
{ TABLE | TABLE_DISTINCT } ( { name dataType = expression } [,...] )
","
Returns the result set. TABLE_DISTINCT removes duplicate rows.
","
SELECT * FROM TABLE(ID INT=(1, 2), NAME VARCHAR=('Hello', 'World'))
"

"Functions (System)","TRANSACTION_ID","
TRANSACTION_ID()
","
Returns the current transaction id for this session.
This method returns NULL if there is no uncommitted change, or if the the database is not persisted.
Otherwise a value of the following form is returned:
""logFileId-position-sessionId"".
This method returns a string.
The value is unique across database restarts (values are not re-used).
","
CALL TRANSACTION_ID()
"

"Functions (System)","TRUNCATE_VALUE","
TRUNCATE_VALUE(value, precisionInt, forceBoolean)
","
Truncate a value to the required precision.
The precision of the returned value may be a bit larger than requested,
because fixed precision values are not truncated (unlike the numeric TRUNCATE method).
Unlike CAST, the truncating a decimal value may lose precision if the force flag is set to true.
The method returns a value with the same data type as the first parameter.
","
CALL TRUNCATE_VALUE(X, 10, TRUE);
"

"Functions (System)","USER","
{ USER | CURRENT_USER } ()
","
Returns the name of the current user of this session.
","
CURRENT_USER()
"

"System Tables","Information Schema","
INFORMATION_SCHEMA
","
To get the list of system tables, execute the statement SELECT * FROM
INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'INFORMATION_SCHEMA'
","

"
"System Tables","Range Table","
SYSTEM_RANGE(start, end)
","
Contains all values from start to end (this is a dynamic table).
","
SYSTEM_RANGE(0, 100)
"