H2Dialect (JBoss Application Server: Build 7.1.2.Final API)

java.lang.Object
- org.hibernate.dialect.Dialect
- - org.hibernate.dialect.H2Dialect

All Implemented Interfaces:

ConversionContext
```
public class H2Dialect
extends Dialect
```
A dialect compatible with the H2 database.

Author:

Thomas Mueller

Field Summary
- Fields inherited from class org.hibernate.dialect.Dialect
  CLOSED_QUOTE, DEFAULT_BATCH_SIZE, LEGACY_LOB_MERGE_STRATEGY, NEW_LOCATOR_LOB_MERGE_STRATEGY, NO_BATCH, QUOTE, STREAM_XFER_LOB_MERGE_STRATEGY

Constructor Summary

Constructors
Constructor and Description

H2Dialect()

Constructors
Constructor and Description
`H2Dialect()`

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`bindLimitParametersFirst()` Does the `LIMIT` clause come at the start of the `SELECT` statement, rather than at the end?
`boolean`	`bindLimitParametersInReverseOrder()` ANSI SQL defines the LIMIT clause to be in the form LIMIT offset, limit.
`boolean`	`doesReadCommittedCauseWritersToBlockReaders()` For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?
`boolean`	`dropTemporaryTableAfterUse()` Do we need to drop the temporary table after use?
`String`	`getAddColumnString()` The syntax used to add a column to a table (optional).
`String`	`getCreateSequenceString(String sequenceName)` Typically dialects which support sequences can create a sequence with a single command.
`String`	`getCreateTemporaryTablePostfix()` Get any fragments needing to be postfixed to the command for temporary table creation.
`String`	`getCreateTemporaryTableString()` Command used to create a temporary table.
`String`	`getCurrentTimestampSelectString()` Retrieve the command used to retrieve the current timestamp from the database.
`String`	`getDropSequenceString(String sequenceName)` Typically dialects which support sequences can drop a sequence with a single command.
`String`	`getForUpdateString()` Get the string to append to SELECT statements to acquire locks for this dialect.
`String`	`getIdentityColumnString()` The syntax used during DDL to define a column as being an IDENTITY.
`String`	`getIdentityInsertString()` The keyword used to insert a generated value into an identity column (or null).
`String`	`getIdentitySelectString()` Get the select command to use to retrieve the last generated IDENTITY value.
`String`	`getLimitString(String sql, boolean hasOffset)` Apply s limit clause to the query.
`String`	`getQuerySequencesString()` Get the select command used retrieve the names of all sequences.
`String`	`getSelectSequenceNextValString(String sequenceName)` Generate the select expression fragment that will retrieve the next value of a sequence as part of another (typically DML) statement.
`String`	`getSequenceNextValString(String sequenceName)` Generate the appropriate select statement to to retrieve the next value of a sequence.
`ViolatedConstraintNameExtracter`	`getViolatedConstraintNameExtracter()`
`boolean`	`isCurrentTimestampSelectStringCallable()` Should the value returned by `Dialect.getCurrentTimestampSelectString()` be treated as callable.
`Boolean`	`performTemporaryTableDDLInIsolation()` Does the dialect require that temporary table DDL statements occur in isolation from other statements? This would be the case if the creation would cause any current transaction to get committed implicitly.
`boolean`	`supportsCurrentTimestampSelection()` Does this dialect support a way to retrieve the database's current timestamp value?
`boolean`	`supportsIdentityColumns()` Does this dialect support identity column key generation?
`boolean`	`supportsIfExistsAfterTableName()`
`boolean`	`supportsLimit()` Does this dialect support some form of limiting query results via a SQL clause?
`boolean`	`supportsLobValueChangePropogation()` Does the dialect support propagating changes to LOB values back to the database? Talking about mutating the internal value of the locator as opposed to supplying a new locator instance...
`boolean`	`supportsPooledSequences()` Does this dialect support "pooled" sequences.
`boolean`	`supportsSequences()` Does this dialect support sequences?
`boolean`	`supportsTemporaryTables()` Does this dialect support temporary tables?
`boolean`	`supportsTupleDistinctCounts()` Does this dialect support `count(distinct a,b)`?
`boolean`	`supportsUnionAll()` Does this dialect support UNION ALL, which is generally a faster variant of UNION?
`boolean`	`supportsUnique()` Does this dialect support the `UNIQUE` column syntax?

Methods inherited from class org.hibernate.dialect.Dialect
appendIdentitySelectToInsert, appendLockHint, applyLocksToSql, areStringComparisonsCaseInsensitive, buildSQLExceptionConversionDelegate, buildSQLExceptionConverter, closeQuote, convertToFirstRowValue, createCaseFragment, createOuterJoinFragment, doesRepeatableReadCauseReadersToBlockWriters, dropConstraints, forceLimitUsage, forUpdateOfColumns, generateTemporaryTableName, getAddForeignKeyConstraintString, getAddPrimaryKeyConstraintString, getAddUniqueConstraintString, getCascadeConstraintsString, getCaseInsensitiveLike, getCastTypeName, getColumnAliasExtractor, getColumnComment, getCreateMultisetTableString, getCreateSequenceString, getCreateSequenceStrings, getCreateSequenceStrings, getCreateTableString, getCrossJoinSeparator, getCurrentTimestampSQLFunctionName, getDefaultProperties, getDialect, getDialect, getDropForeignKeyString, getDropSequenceStrings, getDropTemporaryTableString, getForUpdateNowaitString, getForUpdateNowaitString, getForUpdateString, getForUpdateString, getForUpdateString, getForUpdateString, getFunctions, getHibernateTypeName, getHibernateTypeName, getIdentityColumnString, getIdentitySelectString, getKeywords, getLimitString, getLobMergeStrategy, getLockingStrategy, getLowercaseFunction, getMaxAliasLength, getNativeIdentifierGeneratorClass, getNoColumnsInsertString, getNullColumnString, getReadLockString, getResultSet, getSelectClauseNullString, getSelectGUIDString, getSqlTypeDescriptorOverride, getTableComment, getTableTypeString, getTypeName, getTypeName, getWriteLockString, hasAlterTable, hasDataTypeInIdentityColumn, hasSelfReferentialForeignKeyBug, isLockTimeoutParameterized, openQuote, qualifyIndexName, quote, registerColumnType, registerColumnType, registerFunction, registerHibernateType, registerHibernateType, registerKeyword, registerResultSetOutParameter, remapSqlTypeDescriptor, replaceResultVariableInOrderByClauseWithPosition, requiresCastingOfParametersInSelectClause, supportsBindAsCallableArgument, supportsCascadeDelete, supportsCaseInsensitiveLike, supportsCircularCascadeDeleteConstraints, supportsColumnCheck, supportsCommentOn, supportsEmptyInList, supportsExistsInSelect, supportsExpectedLobUsagePattern, supportsIfExistsBeforeTableName, supportsInsertSelectIdentity, supportsLimitOffset, supportsLockTimeouts, supportsNotNullUnique, supportsOuterJoinForUpdate, supportsParametersInInsertSelect, supportsResultSetPositionQueryMethodsOnForwardOnlyCursor, supportsRowValueConstructorSyntax, supportsRowValueConstructorSyntaxInInList, supportsSubqueryOnMutatingTable, supportsSubselectAsInPredicateLHS, supportsTableCheck, supportsTupleCounts, supportsUnboundedLobLocatorMaterialization, supportsUniqueConstraintInCreateAlterTable, supportsVariableLimit, toBooleanValueString, toString, transformSelectString, useInputStreamToInsertBlob, useMaxForLimit

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - H2Dialect
```
public H2Dialect()
```
- Method Detail
  - getAddColumnString
```
public String getAddColumnString()
```
    Description copied from class: Dialect
    
    The syntax used to add a column to a table (optional).
    
    Overrides:
    
    getAddColumnString in class Dialect
    
    Returns:
    The "add column" fragment.
  - supportsIdentityColumns
```
public boolean supportsIdentityColumns()
```
    Description copied from class: Dialect
    
    Does this dialect support identity column key generation?
    
    Overrides:
    
    supportsIdentityColumns in class Dialect
    
    Returns:
    True if IDENTITY columns are supported; false otherwise.
  - getIdentityColumnString
```
public String getIdentityColumnString()
```
    Description copied from class: Dialect
    
    The syntax used during DDL to define a column as being an IDENTITY.
    
    Overrides:
    
    getIdentityColumnString in class Dialect
    
    Returns:
    The appropriate DDL fragment.
  - getIdentitySelectString
```
public String getIdentitySelectString()
```
    Description copied from class: Dialect
    
    Get the select command to use to retrieve the last generated IDENTITY value.
    
    Overrides:
    
    getIdentitySelectString in class Dialect
    
    Returns:
    The appropriate select command
  - getIdentityInsertString
```
public String getIdentityInsertString()
```
    Description copied from class: Dialect
    
    The keyword used to insert a generated value into an identity column (or null). Need if the dialect does not support inserts that specify no column values.
    
    Overrides:
    
    getIdentityInsertString in class Dialect
    
    Returns:
    The appropriate keyword.
  - getForUpdateString
```
public String getForUpdateString()
```
    Description copied from class: Dialect
    
    Get the string to append to SELECT statements to acquire locks for this dialect.
    
    Overrides:
    
    getForUpdateString in class Dialect
    
    Returns:
    The appropriate FOR UPDATE clause string.
  - supportsUnique
```
public boolean supportsUnique()
```
    Description copied from class: Dialect
    
    Does this dialect support the UNIQUE column syntax?
    
    Overrides:
    
    supportsUnique in class Dialect
    
    Returns:
    boolean
  - supportsLimit
```
public boolean supportsLimit()
```
    Description copied from class: Dialect
    
    Does this dialect support some form of limiting query results via a SQL clause?
    
    Overrides:
    
    supportsLimit in class Dialect
    
    Returns:
    True if this dialect supports some form of LIMIT.
  - getLimitString
```
public String getLimitString(String sql,
                    boolean hasOffset)
```
    Description copied from class: Dialect
    
    Apply s limit clause to the query.
    Typically dialects utilize variable limit clauses when they support limits. Thus, when building the select command we do not actually need to know the limit or the offest since we will just be using placeholders.
    Here we do still pass along whether or not an offset was specified so that dialects not supporting offsets can generate proper exceptions. In general, dialects will override one or the other of this method and Dialect.getLimitString(String, int, int).
    
    Overrides:
    
    getLimitString in class Dialect
    
    Parameters:
    sql - The query to which to apply the limit.
    hasOffset - Is the query requesting an offset?
    
    Returns:
    the modified SQL
  - bindLimitParametersInReverseOrder
```
public boolean bindLimitParametersInReverseOrder()
```
    Description copied from class: Dialect
    
    ANSI SQL defines the LIMIT clause to be in the form LIMIT offset, limit. Does this dialect require us to bind the parameters in reverse order?
    
    Overrides:
    
    bindLimitParametersInReverseOrder in class Dialect
    
    Returns:
    true if the correct order is limit, offset
  - bindLimitParametersFirst
```
public boolean bindLimitParametersFirst()
```
    Description copied from class: Dialect
    
    Does the LIMIT clause come at the start of the SELECT statement, rather than at the end?
    
    Overrides:
    
    bindLimitParametersFirst in class Dialect
    
    Returns:
    true if limit parameters should come before other parameters
  - supportsIfExistsAfterTableName
```
public boolean supportsIfExistsAfterTableName()
```
    Overrides:
    
    supportsIfExistsAfterTableName in class Dialect
  - supportsSequences
```
public boolean supportsSequences()
```
    Description copied from class: Dialect
    
    Does this dialect support sequences?
    
    Overrides:
    
    supportsSequences in class Dialect
    
    Returns:
    True if sequences supported; false otherwise.
  - supportsPooledSequences
```
public boolean supportsPooledSequences()
```
    Description copied from class: Dialect
    
    Does this dialect support "pooled" sequences. Not aware of a better name for this. Essentially can we specify the initial and increment values?
    
    Overrides:
    
    supportsPooledSequences in class Dialect
    
    Returns:
    True if such "pooled" sequences are supported; false otherwise.
    See Also:
    Dialect.getCreateSequenceStrings(String, int, int), Dialect.getCreateSequenceString(String, int, int)
  - getCreateSequenceString
```
public String getCreateSequenceString(String sequenceName)
```
    Description copied from class: Dialect
    
    Typically dialects which support sequences can create a sequence with a single command. This is convenience form of Dialect.getCreateSequenceStrings(java.lang.String) to help facilitate that.
    Dialects which support sequences and can create a sequence in a single command need *only* override this method. Dialects which support sequences but require multiple commands to create a sequence should instead override Dialect.getCreateSequenceStrings(java.lang.String).
    
    Overrides:
    
    getCreateSequenceString in class Dialect
    
    Parameters:
    sequenceName - The name of the sequence
    
    Returns:
    The sequence creation command
  - getDropSequenceString
```
public String getDropSequenceString(String sequenceName)
```
    Description copied from class: Dialect
    
    Typically dialects which support sequences can drop a sequence with a single command. This is convenience form of Dialect.getDropSequenceStrings(java.lang.String) to help facilitate that.
    Dialects which support sequences and can drop a sequence in a single command need *only* override this method. Dialects which support sequences but require multiple commands to drop a sequence should instead override Dialect.getDropSequenceStrings(java.lang.String).
    
    Overrides:
    
    getDropSequenceString in class Dialect
    
    Parameters:
    sequenceName - The name of the sequence
    
    Returns:
    The sequence drop commands
  - getSelectSequenceNextValString
```
public String getSelectSequenceNextValString(String sequenceName)
```
    Description copied from class: Dialect
    
    Generate the select expression fragment that will retrieve the next value of a sequence as part of another (typically DML) statement.
    This differs from Dialect.getSequenceNextValString(String) in that this should return an expression usable within another statement.
    
    Overrides:
    
    getSelectSequenceNextValString in class Dialect
    
    Parameters:
    sequenceName - the name of the sequence
    
    Returns:
    The "nextval" fragment.
  - getSequenceNextValString
```
public String getSequenceNextValString(String sequenceName)
```
    Description copied from class: Dialect
    
    Generate the appropriate select statement to to retrieve the next value of a sequence.
    This should be a "stand alone" select statement.
    
    Overrides:
    
    getSequenceNextValString in class Dialect
    
    Parameters:
    sequenceName - the name of the sequence
    
    Returns:
    String The "nextval" select string.
  - getQuerySequencesString
```
public String getQuerySequencesString()
```
    Description copied from class: Dialect
    
    Get the select command used retrieve the names of all sequences.
    
    Overrides:
    
    getQuerySequencesString in class Dialect
    
    Returns:
    The select command; or null if sequences are not supported.
    See Also:
    SchemaUpdate
  - getViolatedConstraintNameExtracter
```
public ViolatedConstraintNameExtracter getViolatedConstraintNameExtracter()
```
    Specified by:
    
    getViolatedConstraintNameExtracter in interface ConversionContext
    
    Overrides:
    
    getViolatedConstraintNameExtracter in class Dialect
  - supportsTemporaryTables
```
public boolean supportsTemporaryTables()
```
    Description copied from class: Dialect
    
    Does this dialect support temporary tables?
    
    Overrides:
    
    supportsTemporaryTables in class Dialect
    
    Returns:
    True if temp tables are supported; false otherwise.
  - getCreateTemporaryTableString
```
public String getCreateTemporaryTableString()
```
    Description copied from class: Dialect
    
    Command used to create a temporary table.
    
    Overrides:
    
    getCreateTemporaryTableString in class Dialect
    
    Returns:
    The command used to create a temporary table.
  - getCreateTemporaryTablePostfix
```
public String getCreateTemporaryTablePostfix()
```
    Description copied from class: Dialect
    
    Get any fragments needing to be postfixed to the command for temporary table creation.
    
    Overrides:
    
    getCreateTemporaryTablePostfix in class Dialect
    
    Returns:
    Any required postfix.
  - performTemporaryTableDDLInIsolation
```
public Boolean performTemporaryTableDDLInIsolation()
```
    Description copied from class: Dialect
    Does the dialect require that temporary table DDL statements occur in isolation from other statements? This would be the case if the creation would cause any current transaction to get committed implicitly.
    JDBC defines a standard way to query for this information via the DatabaseMetaData.dataDefinitionCausesTransactionCommit() method. However, that does not distinguish between temporary table DDL and other forms of DDL; MySQL, for example, reports DDL causing a transaction commit via its driver, even though that is not the case for temporary table DDL.
    Possible return values and their meanings:
    - Boolean.TRUE - Unequivocally, perform the temporary table DDL in isolation.
    - Boolean.FALSE - Unequivocally, do not perform the temporary table DDL in isolation.
    - null - defer to the JDBC driver response in regards to DatabaseMetaData.dataDefinitionCausesTransactionCommit()
    Overrides:
    
    performTemporaryTableDDLInIsolation in class Dialect
    
    Returns:
    see the result matrix above.
  - dropTemporaryTableAfterUse
```
public boolean dropTemporaryTableAfterUse()
```
    Description copied from class: Dialect
    
    Do we need to drop the temporary table after use?
    
    Overrides:
    
    dropTemporaryTableAfterUse in class Dialect
    
    Returns:
    True if the table should be dropped.
  - supportsCurrentTimestampSelection
```
public boolean supportsCurrentTimestampSelection()
```
    Description copied from class: Dialect
    
    Does this dialect support a way to retrieve the database's current timestamp value?
    
    Overrides:
    
    supportsCurrentTimestampSelection in class Dialect
    
    Returns:
    True if the current timestamp can be retrieved; false otherwise.
  - isCurrentTimestampSelectStringCallable
```
public boolean isCurrentTimestampSelectStringCallable()
```
    Description copied from class: Dialect
    
    Should the value returned by Dialect.getCurrentTimestampSelectString() be treated as callable. Typically this indicates that JDBC escape syntax is being used...
    
    Overrides:
    
    isCurrentTimestampSelectStringCallable in class Dialect
    
    Returns:
    True if the Dialect.getCurrentTimestampSelectString() return is callable; false otherwise.
  - getCurrentTimestampSelectString
```
public String getCurrentTimestampSelectString()
```
    Description copied from class: Dialect
    
    Retrieve the command used to retrieve the current timestamp from the database.
    
    Overrides:
    
    getCurrentTimestampSelectString in class Dialect
    
    Returns:
    The command.
  - supportsUnionAll
```
public boolean supportsUnionAll()
```
    Description copied from class: Dialect
    
    Does this dialect support UNION ALL, which is generally a faster variant of UNION?
    
    Overrides:
    
    supportsUnionAll in class Dialect
    
    Returns:
    True if UNION ALL is supported; false otherwise.
  - supportsLobValueChangePropogation
```
public boolean supportsLobValueChangePropogation()
```
    Description copied from class: Dialect
    
    Does the dialect support propagating changes to LOB values back to the database? Talking about mutating the internal value of the locator as opposed to supplying a new locator instance...
    For BLOBs, the internal value might be changed by: Blob.setBinaryStream(long), Blob.setBytes(long, byte[]), Blob.setBytes(long, byte[], int, int), or Blob.truncate(long).
    For CLOBs, the internal value might be changed by: Clob.setAsciiStream(long), Clob.setCharacterStream(long), Clob.setString(long, String), Clob.setString(long, String, int, int), or Clob.truncate(long).
    NOTE : I do not know the correct answer currently for databases which (1) are not part of the cruise control process or (2) do not Dialect.supportsExpectedLobUsagePattern().
    
    Overrides:
    
    supportsLobValueChangePropogation in class Dialect
    
    Returns:
    True if the changes are propagated back to the database; false otherwise.
  - supportsTupleDistinctCounts
```
public boolean supportsTupleDistinctCounts()
```
    Description copied from class: Dialect
    
    Does this dialect support `count(distinct a,b)`?
    
    Overrides:
    
    supportsTupleDistinctCounts in class Dialect
    
    Returns:
    True if the database supports counting distinct tuples; false otherwise.
  - doesReadCommittedCauseWritersToBlockReaders
```
public boolean doesReadCommittedCauseWritersToBlockReaders()
```
    Description copied from class: Dialect
    
    For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?
    
    Overrides:
    
    doesReadCommittedCauseWritersToBlockReaders in class Dialect
    
    Returns:
    True if writers block readers to achieve READ_COMMITTED; false otherwise.

Class H2Dialect

Field Summary

Fields inherited from class org.hibernate.dialect.Dialect

Constructor Summary

Method Summary

Methods inherited from class org.hibernate.dialect.Dialect

Methods inherited from class java.lang.Object

Constructor Detail

H2Dialect

Method Detail

getAddColumnString

supportsIdentityColumns

getIdentityColumnString

getIdentitySelectString

getIdentityInsertString

getForUpdateString

supportsUnique

supportsLimit

getLimitString

bindLimitParametersInReverseOrder

bindLimitParametersFirst

supportsIfExistsAfterTableName

supportsSequences

supportsPooledSequences

getCreateSequenceString

getDropSequenceString

getSelectSequenceNextValString

getSequenceNextValString

getQuerySequencesString

getViolatedConstraintNameExtracter

supportsTemporaryTables

getCreateTemporaryTableString

getCreateTemporaryTablePostfix

performTemporaryTableDDLInIsolation

dropTemporaryTableAfterUse

supportsCurrentTimestampSelection

isCurrentTimestampSelectStringCallable

getCurrentTimestampSelectString

supportsUnionAll

supportsLobValueChangePropogation

supportsTupleDistinctCounts

doesReadCommittedCauseWritersToBlockReaders