DB2Dialect (Hibernate JavaDocs)

java.lang.Object
- org.hibernate.dialect.Dialect
- - org.hibernate.dialect.DB2Dialect

All Implemented Interfaces:

ConversionContext

Direct Known Subclasses:

DB2390Dialect, DB2400Dialect, DB297Dialect, DB2SpatialDialect, DerbyDialect
```
public class DB2Dialect
extends Dialect
```
An SQL dialect for DB2.

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, STANDARD_DEFAULT_BATCH_LOAD_SIZING_STRATEGY, STREAM_XFER_LOB_MERGE_STRATEGY, TWO_SINGLE_QUOTES_REPLACEMENT

Constructor Summary

Constructors
Constructor and Description

DB2Dialect()
Constructs a DB2Dialect

Constructors
Constructor and Description
`DB2Dialect()` Constructs a DB2Dialect

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`SQLExceptionConversionDelegate`	`buildSQLExceptionConversionDelegate()` Build an instance of a `SQLExceptionConversionDelegate` for interpreting dialect-specific error or SQLState codes.
`int`	`convertToFirstRowValue(int zeroBasedFirstResult)` Hibernate APIs explicitly state that setFirstResult() should be a zero-based offset.
`boolean`	`doesReadCommittedCauseWritersToBlockReaders()` For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?
`boolean`	`dropConstraints()` Do we need to drop constraints before dropping tables in this dialect?
`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`	`getCrossJoinSeparator()` Returns the separator to use for defining cross joins when translating HQL queries.
`String`	`getCurrentTimestampSelectString()` Retrieve the command used to retrieve the current timestamp from the database.
`MultiTableBulkIdStrategy`	`getDefaultMultiTableBulkIdStrategy()`
`String[]`	`getDropSchemaCommand(String schemaName)` Get the SQL command used to drop the named schema
`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.
`IdentityColumnSupport`	`getIdentityColumnSupport()` Get the appropriate `IdentityColumnSupport`
`LimitHandler`	`getLimitHandler()` Returns the delegate managing LIMIT clause.
`String`	`getLimitString(String sql, int offset, int limit)` Given a limit and an offset, apply the limit clause to the query.
`String`	`getLowercaseFunction()` The name of the SQL function that transforms a string to lowercase
`String`	`getNotExpression(String expression)` Negate an expression
`String`	`getQuerySequencesString()` Get the select command used retrieve the names of all sequences.
`ResultSet`	`getResultSet(CallableStatement ps)` Given a callable statement previously processed by `Dialect.registerResultSetOutParameter(java.sql.CallableStatement, int)`, extract the `ResultSet` from the OUT parameter.
`String`	`getSelectClauseNullString(int sqlType)` Given a `Types` type code, determine an appropriate null value to use in a select clause.
`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.
`SequenceInformationExtractor`	`getSequenceInformationExtractor()`
`String`	`getSequenceNextValString(String sequenceName)` Generate the appropriate select statement to to retrieve the next value of a sequence.
`protected SqlTypeDescriptor`	`getSqlTypeDescriptorOverride(int sqlCode)` Returns the `SqlTypeDescriptor` that should be used to handle the given JDBC type code.
`UniqueDelegate`	`getUniqueDelegate()` Get the UniqueDelegate supported by this dialect
`boolean`	`isCurrentTimestampSelectStringCallable()` Should the value returned by `Dialect.getCurrentTimestampSelectString()` be treated as callable.
`int`	`registerResultSetOutParameter(CallableStatement statement, int col)` Registers a parameter (either OUT, or the new REF_CURSOR param type available in Java 8) capable of returning `ResultSet` by position.
`String`	`renderOrderByElement(String expression, String collation, String order, NullPrecedence nullPrecedence)` Handle DB2 "support" for null precedence...
`boolean`	`requiresCastingOfParametersInSelectClause()` Does this dialect require that parameters appearing in the `SELECT` clause be wrapped in `cast()` calls to tell the db parser the expected type.
`boolean`	`supportsCommentOn()` Does this dialect/database support commenting on tables, columns, etc?
`boolean`	`supportsCurrentTimestampSelection()` Does this dialect support a way to retrieve the database's current timestamp value?
`boolean`	`supportsEmptyInList()` Does this dialect support empty IN lists? For example, is [where XYZ in ()] a supported construct?
`boolean`	`supportsExistsInSelect()` Does the dialect support an exists statement in the select clause?
`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`	`supportsLockTimeouts()` Informational metadata about whether this dialect is known to support specifying timeouts for requested lock acquisitions.
`boolean`	`supportsOuterJoinForUpdate()` Does this dialect support `FOR UPDATE` in conjunction with outer joined rows?
`boolean`	`supportsParametersInInsertSelect()` Does this dialect support parameters within the `SELECT` clause of `INSERT ...`
`boolean`	`supportsPartitionBy()` Does the underlying database support partition by
`boolean`	`supportsPooledSequences()` Does this dialect support "pooled" sequences.
`boolean`	`supportsResultSetPositionQueryMethodsOnForwardOnlyCursor()` Does this dialect support asking the result set its positioning information on forward only cursors.
`boolean`	`supportsSequences()` Does this dialect support sequences?
`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`	`supportsVariableLimit()` Does this dialect support bind variables (i.e., prepared statement parameters) for its limit/offset?
`boolean`	`useMaxForLimit()` Does the `LIMIT` clause take a "maximum" row number instead of a total number of returned rows? This is easiest understood via an example.

Methods inherited from class org.hibernate.dialect.Dialect
addSqlHintOrComment, appendLockHint, appendLockHint, applyLocksToSql, areStringComparisonsCaseInsensitive, augmentRecognizedTableTypes, bindLimitParametersFirst, bindLimitParametersInReverseOrder, buildIdentifierHelper, buildSQLExceptionConverter, canCreateCatalog, canCreateSchema, cast, cast, cast, closeQuote, contributeTypes, createCaseFragment, createOuterJoinFragment, defaultScrollMode, doesRepeatableReadCauseReadersToBlockWriters, equivalentTypes, escapeComment, escapeLiteral, forceLimitUsage, forceLobAsLastValue, forUpdateOfColumns, getAddColumnSuffixString, getAddForeignKeyConstraintString, getAddForeignKeyConstraintString, getAddPrimaryKeyConstraintString, getAddUniqueConstraintString, getAlterTableString, getAuxiliaryDatabaseObjectExporter, getCallableStatementSupport, getCascadeConstraintsString, getCaseInsensitiveLike, getCastTypeName, getColumnAliasExtractor, getColumnComment, getCreateCatalogCommand, getCreateMultisetTableString, getCreateSchemaCommand, getCreateSequenceString, getCreateSequenceStrings, getCreateSequenceStrings, getCreateTableString, getCreateTemporaryTableColumnAnnotation, getCurrentSchemaCommand, getCurrentTimestampSQLFunctionName, getDefaultBatchLoadSizingStrategy, getDefaultProperties, getDialect, getDialect, getDropCatalogCommand, getDropForeignKeyString, getDropSequenceStrings, getDropTableString, getForeignKeyExporter, getForUpdateNowaitString, getForUpdateNowaitString, getForUpdateSkipLockedString, getForUpdateSkipLockedString, getForUpdateString, getForUpdateString, getForUpdateString, getForUpdateString, getFunctions, getHibernateTypeName, getHibernateTypeName, getIndexExporter, getInExpressionCountLimit, getKeywords, getLimitString, getLobMergeStrategy, getLockingStrategy, getMaxAliasLength, getNameQualifierSupport, getNativeIdentifierGeneratorClass, getNativeIdentifierGeneratorStrategy, getNoColumnsInsertString, getNullColumnString, getQueryHintString, getQueryHintString, getReadLockString, getReadLockString, getResultSet, getResultSet, getSchemaNameResolver, getSelectGUIDString, getSequenceExporter, getTableComment, getTableExporter, getTableTypeString, getTypeName, getTypeName, getUniqueKeyExporter, getViolatedConstraintNameExtracter, getWriteLockString, getWriteLockString, hasAlterTable, hasSelfReferentialForeignKeyBug, inlineLiteral, isJdbcLogWarningsEnabledByDefault, isLegacyLimitHandlerBehaviorEnabled, isLockTimeoutParameterized, isTypeNameRegistered, openQuote, prependComment, qualifyIndexName, quote, registerColumnType, registerColumnType, registerFunction, registerHibernateType, registerHibernateType, registerKeyword, registerResultSetOutParameter, remapSqlTypeDescriptor, replaceResultVariableInOrderByClauseWithPosition, requiresParensForTupleDistinctCounts, supportsBindAsCallableArgument, supportsCascadeDelete, supportsCaseInsensitiveLike, supportsCircularCascadeDeleteConstraints, supportsColumnCheck, supportsExpectedLobUsagePattern, supportsIfExistsAfterAlterTable, supportsIfExistsAfterConstraintName, supportsIfExistsAfterTableName, supportsIfExistsBeforeConstraintName, supportsIfExistsBeforeTableName, supportsJdbcConnectionLobCreation, supportsLimitOffset, supportsNamedParameters, supportsNationalizedTypes, supportsNoColumnsInsert, supportsNonQueryWithCTE, supportsNotNullUnique, supportsNoWait, supportsRowValueConstructorSyntax, supportsRowValueConstructorSyntaxInInList, supportsRowValueConstructorSyntaxInSet, supportsSelectAliasInGroupByClause, supportsSkipLocked, supportsSubqueryOnMutatingTable, supportsSubselectAsInPredicateLHS, supportsTableCheck, supportsTupleCounts, supportsTuplesInSubqueries, supportsUnboundedLobLocatorMaterialization, supportsUnique, supportsUniqueConstraintInCreateAlterTable, supportsValuesList, toBooleanValueString, toString, transformSelectString, useFollowOnLocking, useFollowOnLocking, useInputStreamToInsertBlob

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

- Constructor Detail
  - DB2Dialect
```
public DB2Dialect()
```
    Constructs a DB2Dialect
- Method Detail
  - getLowercaseFunction
```
public String getLowercaseFunction()
```
    Description copied from class: Dialect
    
    The name of the SQL function that transforms a string to lowercase
    
    Overrides:
    
    getLowercaseFunction in class Dialect
    
    Returns:
    
    The dialect-specific lowercase function.
  - 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.
  - dropConstraints
```
public boolean dropConstraints()
```
    Description copied from class: Dialect
    
    Do we need to drop constraints before dropping tables in this dialect?
    
    Overrides:
    
    dropConstraints in class Dialect
    
    Returns:
    
    True if constraints must be dropped prior to dropping the table; false otherwise.
  - getDropSchemaCommand
```
public String[] getDropSchemaCommand(String schemaName)
```
    Description copied from class: Dialect
    
    Get the SQL command used to drop the named schema
    
    Overrides:
    
    getDropSchemaCommand in class Dialect
    
    Parameters:
    
    schemaName - The name of the schema to be dropped.
    
    Returns:
    
    The drop commands
  - 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.
  - getSelectSequenceNextValString
```
public String getSelectSequenceNextValString(String sequenceName)
                                      throws MappingException
```
    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.
    
    Throws:
    
    MappingException - If sequences are not supported.
  - 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
  - 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)
  - 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
  - getSequenceInformationExtractor
```
public SequenceInformationExtractor getSequenceInformationExtractor()
```
    Overrides:
    
    getSequenceInformationExtractor in class Dialect
  - 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.
  - supportsVariableLimit
```
public boolean supportsVariableLimit()
```
    Description copied from class: Dialect
    
    Does this dialect support bind variables (i.e., prepared statement parameters) for its limit/offset?
    
    Overrides:
    
    supportsVariableLimit in class Dialect
    
    Returns:
    
    True if bind variables can be used; false otherwise.
  - getLimitString
```
public String getLimitString(String sql,
                             int offset,
                             int limit)
```
    Description copied from class: Dialect
    
    Given a limit and an offset, apply the limit clause to the query.
    
    Overrides:
    
    getLimitString in class Dialect
    
    Parameters:
    
    sql - The query to which to apply the limit.
    
    offset - The offset of the limit
    
    limit - The limit of the limit ;)
    
    Returns:
    
    The modified query statement with the limit applied.
  - convertToFirstRowValue
```
public int convertToFirstRowValue(int zeroBasedFirstResult)
```
    Hibernate APIs explicitly state that setFirstResult() should be a zero-based offset. Here we allow the Dialect a chance to convert that value based on what the underlying db or driver will expect.
    NOTE: what gets passed into Dialect.getLimitString(String,int,int) is the zero-based offset. Dialects which do not Dialect.supportsVariableLimit() should take care to perform any needed first-row-conversion calls prior to injecting the limit values into the SQL string.
    DB2 does have a one-based offset, however this was actually already handled in the limit string building (the '?+1' bit). To not mess up inheritors, I'll leave that part alone and not touch the offset here.
    
    Overrides:
    
    convertToFirstRowValue in class Dialect
    
    Parameters:
    
    zeroBasedFirstResult - The user-supplied, zero-based first row offset.
    
    Returns:
    
    The corresponding db/dialect specific offset.
    
    See Also:
    
    Query.setFirstResult(int), Criteria.setFirstResult(int)
  - 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.
  - useMaxForLimit
```
public boolean useMaxForLimit()
```
    Description copied from class: Dialect
    
    Does the LIMIT clause take a "maximum" row number instead of a total number of returned rows?
    This is easiest understood via an example. Consider you have a table with 20 rows, but you only want to retrieve rows number 11 through 20. Generally, a limit with offset would say that the offset = 11 and the limit = 10 (we only want 10 rows at a time); this is specifying the total number of returned rows. Some dialects require that we instead specify offset = 11 and limit = 20, where 20 is the "last" row we want relative to offset (i.e. total number of rows = 20 - 11 = 9)
    So essentially, is limit relative from offset? Or is limit absolute?
    
    Overrides:
    
    useMaxForLimit in class Dialect
    
    Returns:
    
    True if limit is relative from offset; false otherwise.
  - supportsOuterJoinForUpdate
```
public boolean supportsOuterJoinForUpdate()
```
    Description copied from class: Dialect
    
    Does this dialect support FOR UPDATE in conjunction with outer joined rows?
    
    Overrides:
    
    supportsOuterJoinForUpdate in class Dialect
    
    Returns:
    
    True if outer joined rows can be locked via FOR UPDATE.
  - supportsExistsInSelect
```
public boolean supportsExistsInSelect()
```
    Description copied from class: Dialect
    
    Does the dialect support an exists statement in the select clause?
    
    Overrides:
    
    supportsExistsInSelect in class Dialect
    
    Returns:
    
    True if exists checks are allowed in the select clause; false otherwise.
  - supportsLockTimeouts
```
public boolean supportsLockTimeouts()
```
    Description copied from class: Dialect
    
    Informational metadata about whether this dialect is known to support specifying timeouts for requested lock acquisitions.
    
    Overrides:
    
    supportsLockTimeouts in class Dialect
    
    Returns:
    
    True is this dialect supports specifying lock timeouts.
  - getSelectClauseNullString
```
public String getSelectClauseNullString(int sqlType)
```
    Description copied from class: Dialect
    
    Given a Types type code, determine an appropriate null value to use in a select clause.
    One thing to consider here is that certain databases might require proper casting for the nulls here since the select here will be part of a UNION/UNION ALL.
    
    Overrides:
    
    getSelectClauseNullString in class Dialect
    
    Parameters:
    
    sqlType - The Types type code.
    
    Returns:
    
    The appropriate select clause value fragment.
  - 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.
  - registerResultSetOutParameter
```
public int registerResultSetOutParameter(CallableStatement statement,
                                         int col)
                                  throws SQLException
```
    Description copied from class: Dialect
    
    Registers a parameter (either OUT, or the new REF_CURSOR param type available in Java 8) capable of returning ResultSet *by position*. Pre-Java 8, registering such ResultSet-returning parameters varied greatly across database and drivers; hence its inclusion as part of the Dialect contract.
    
    Overrides:
    
    registerResultSetOutParameter in class Dialect
    
    Parameters:
    
    statement - The callable statement.
    
    col - The bind position at which to register the output param.
    
    Returns:
    
    The number of (contiguous) bind positions used.
    
    Throws:
    
    SQLException - Indicates problems registering the param.
  - getResultSet
```
public ResultSet getResultSet(CallableStatement ps)
                       throws SQLException
```
    Description copied from class: Dialect
    
    Given a callable statement previously processed by Dialect.registerResultSetOutParameter(java.sql.CallableStatement, int), extract the ResultSet from the OUT parameter.
    
    Overrides:
    
    getResultSet in class Dialect
    
    Parameters:
    
    ps - The callable statement.
    
    Returns:
    
    The extracted result set.
    
    Throws:
    
    SQLException - Indicates problems extracting the result set.
  - supportsCommentOn
```
public boolean supportsCommentOn()
```
    Description copied from class: Dialect
    
    Does this dialect/database support commenting on tables, columns, etc?
    
    Overrides:
    
    supportsCommentOn in class Dialect
    
    Returns:
    
    true if commenting is supported
  - getDefaultMultiTableBulkIdStrategy
```
public MultiTableBulkIdStrategy getDefaultMultiTableBulkIdStrategy()
```
    Overrides:
    
    getDefaultMultiTableBulkIdStrategy in class Dialect
  - 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.
  - 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.
  - 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.
  - supportsParametersInInsertSelect
```
public boolean supportsParametersInInsertSelect()
```
    Does this dialect support parameters within the SELECT clause of INSERT ... SELECT ... statements?
    NOTE : DB2 is known to support parameters in the SELECT clause, but only in casted form (see requiresCastingOfParametersInSelectClause()).
    
    Overrides:
    
    supportsParametersInInsertSelect in class Dialect
    
    Returns:
    
    True if this is supported; false otherwise.
  - requiresCastingOfParametersInSelectClause
```
public boolean requiresCastingOfParametersInSelectClause()
```
    Does this dialect require that parameters appearing in the SELECT clause be wrapped in cast() calls to tell the db parser the expected type.
    DB2 in fact does require that parameters appearing in the select clause be wrapped in cast() calls to tell the DB parser the type of the select value.
    
    Overrides:
    
    requiresCastingOfParametersInSelectClause in class Dialect
    
    Returns:
    
    True if select clause parameter must be cast()ed
  - supportsResultSetPositionQueryMethodsOnForwardOnlyCursor
```
public boolean supportsResultSetPositionQueryMethodsOnForwardOnlyCursor()
```
    Description copied from class: Dialect
    
    Does this dialect support asking the result set its positioning information on forward only cursors. Specifically, in the case of scrolling fetches, Hibernate needs to use ResultSet.isAfterLast() and ResultSet.isBeforeFirst(). Certain drivers do not allow access to these methods for forward only cursors.
    NOTE : this is highly driver dependent!
    
    Overrides:
    
    supportsResultSetPositionQueryMethodsOnForwardOnlyCursor in class Dialect
    
    Returns:
    
    True if methods like ResultSet.isAfterLast() and ResultSet.isBeforeFirst() are supported for forward only cursors; false otherwise.
  - getCrossJoinSeparator
```
public String getCrossJoinSeparator()
```
    Description copied from class: Dialect
    
    Returns the separator to use for defining cross joins when translating HQL queries.
    Typically this will be either [ cross join ] or [, ]
    Note that the spaces are important!
    
    Overrides:
    
    getCrossJoinSeparator in class Dialect
    
    Returns:
    
    The cross join separator
  - supportsEmptyInList
```
public boolean supportsEmptyInList()
```
    Description copied from class: Dialect
    
    Does this dialect support empty IN lists?
    For example, is [where XYZ in ()] a supported construct?
    
    Overrides:
    
    supportsEmptyInList in class Dialect
    
    Returns:
    
    True if empty in lists are 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.
  - 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.
  - 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.
  - getSqlTypeDescriptorOverride
```
protected SqlTypeDescriptor getSqlTypeDescriptorOverride(int sqlCode)
```
    Description copied from class: Dialect
    
    Returns the SqlTypeDescriptor that should be used to handle the given JDBC type code. Returns null if there is no override.
    
    Overrides:
    
    getSqlTypeDescriptorOverride in class Dialect
    
    Parameters:
    
    sqlCode - A Types constant indicating the SQL column type
    
    Returns:
    
    The SqlTypeDescriptor to use as an override, or null if there is no override.
  - buildSQLExceptionConversionDelegate
```
public SQLExceptionConversionDelegate buildSQLExceptionConversionDelegate()
```
    Description copied from class: Dialect
    Build an instance of a SQLExceptionConversionDelegate for interpreting dialect-specific error or SQLState codes.
    When Dialect.buildSQLExceptionConverter() returns null, the default SQLExceptionConverter is used to interpret SQLState and error codes. If this method is overridden to return a non-null value, the default SQLExceptionConverter will use the returned SQLExceptionConversionDelegate in addition to the following standard delegates:
    1. a "static" delegate based on the JDBC 4 defined SQLException hierarchy;
    2. a delegate that interprets SQLState codes for either X/Open or SQL-2003 codes, depending on java.sql.DatabaseMetaData#getSQLStateType
    It is strongly recommended that specific Dialect implementations override this method, since interpretation of a SQL error is much more accurate when based on the vendor-specific ErrorCode rather than the SQLState.
    Specific Dialects may override to return whatever is most appropriate for that vendor.
    Overrides:
    
    buildSQLExceptionConversionDelegate in class Dialect
    
    Returns:
    
    The SQLExceptionConversionDelegate for this dialect
  - getUniqueDelegate
```
public UniqueDelegate getUniqueDelegate()
```
    Description copied from class: Dialect
    
    Get the UniqueDelegate supported by this dialect
    
    Overrides:
    
    getUniqueDelegate in class Dialect
    
    Returns:
    
    The UniqueDelegate
  - getNotExpression
```
public String getNotExpression(String expression)
```
    Description copied from class: Dialect
    
    Negate an expression
    
    Overrides:
    
    getNotExpression in class Dialect
    
    Parameters:
    
    expression - The expression to negate
    
    Returns:
    
    The negated expression
  - getLimitHandler
```
public LimitHandler getLimitHandler()
```
    Description copied from class: Dialect
    
    Returns the delegate managing LIMIT clause.
    
    Overrides:
    
    getLimitHandler in class Dialect
    
    Returns:
    
    LIMIT clause delegate.
  - renderOrderByElement
```
public String renderOrderByElement(String expression,
                                   String collation,
                                   String order,
                                   NullPrecedence nullPrecedence)
```
    Handle DB2 "support" for null precedence...
    
    Overrides:
    
    renderOrderByElement in class Dialect
    
    Parameters:
    
    expression - The SQL order expression. In case of @OrderBy annotation user receives property placeholder (e.g. attribute name enclosed in '{' and '}' signs).
    
    collation - Collation string in format collate IDENTIFIER, or null if expression has not been explicitly specified.
    
    order - Order direction. Possible values: asc, desc, or null if expression has not been explicitly specified.
    
    nullPrecedence - Nulls precedence. Default value: NullPrecedence.NONE.
    
    Returns:
    
    SQL string.
  - getIdentityColumnSupport
```
public IdentityColumnSupport getIdentityColumnSupport()
```
    Description copied from class: Dialect
    
    Get the appropriate IdentityColumnSupport
    
    Overrides:
    
    getIdentityColumnSupport in class Dialect
    
    Returns:
    
    the IdentityColumnSupport
  - supportsPartitionBy
```
public boolean supportsPartitionBy()
```
    Description copied from class: Dialect
    
    Does the underlying database support partition by
    
    Overrides:
    
    supportsPartitionBy in class Dialect
    
    Returns:
    
    boolean

Class DB2Dialect

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

DB2Dialect

Method Detail

getLowercaseFunction

getAddColumnString

dropConstraints

getDropSchemaCommand

getSequenceNextValString

getSelectSequenceNextValString

getCreateSequenceString

getDropSequenceString

supportsSequences

supportsPooledSequences

getQuerySequencesString

getSequenceInformationExtractor

supportsLimit

supportsVariableLimit

getLimitString

convertToFirstRowValue

getForUpdateString

useMaxForLimit

supportsOuterJoinForUpdate

supportsExistsInSelect

supportsLockTimeouts

getSelectClauseNullString

supportsUnionAll

registerResultSetOutParameter

getResultSet

supportsCommentOn

getDefaultMultiTableBulkIdStrategy

supportsCurrentTimestampSelection

getCurrentTimestampSelectString

isCurrentTimestampSelectStringCallable

supportsParametersInInsertSelect

requiresCastingOfParametersInSelectClause

supportsResultSetPositionQueryMethodsOnForwardOnlyCursor

getCrossJoinSeparator

supportsEmptyInList

supportsLobValueChangePropogation

doesReadCommittedCauseWritersToBlockReaders

supportsTupleDistinctCounts

getSqlTypeDescriptorOverride

buildSQLExceptionConversionDelegate

getUniqueDelegate

getNotExpression

getLimitHandler

renderOrderByElement

getIdentityColumnSupport

supportsPartitionBy