MySQLDialect (Hibernate JavaDocs)

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

All Implemented Interfaces:

ConversionContext

Direct Known Subclasses:

MySQL5Dialect, MySQLInnoDBDialect, MySQLMyISAMDialect
```
public class MySQLDialect
extends Dialect
```
An SQL dialect for MySQL (prior to 5.x).

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

MySQLDialect()

Constructors
Constructor and Description
`MySQLDialect()`

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`areStringComparisonsCaseInsensitive()` Are string comparisons implicitly case insensitive.
`SQLExceptionConversionDelegate`	`buildSQLExceptionConversionDelegate()` Build an instance of a `SQLExceptionConversionDelegate` for interpreting dialect-specific error or SQLState codes.
`char`	`closeQuote()` The character specific to this dialect used to close a quoted identifier.
`String`	`getAddColumnString()` The syntax used to add a column to a table (optional).
`String`	`getAddForeignKeyConstraintString(String constraintName, String[] foreignKey, String referencedTable, String[] primaryKey, boolean referencesPrimaryKey)` The syntax used to add a foreign key constraint to a table.
`String`	`getCastTypeName(int code)` Get the name of the database type appropriate for casting operations (via the CAST() SQL function) for the given `Types` typecode.
`String`	`getColumnComment(String comment)`
`String`	`getCreateTemporaryTableString()` Command used to create a temporary table.
`String`	`getCurrentTimestampSelectString()` Retrieve the command used to retrieve the current timestamp from the database.
`String`	`getDropForeignKeyString()`
`String`	`getDropTemporaryTableString()` Command used to drop a temporary table.
`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`	`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`	`getNotExpression(String expression)`
`String`	`getReadLockString(int timeout)` Get the string to append to SELECT statements to acquire WRITE locks for this dialect.
`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`	`getSelectGUIDString()` Get the command used to select a GUID from the underlying database.
`String`	`getTableComment(String comment)`
`String`	`getWriteLockString(int timeout)` Get the string to append to SELECT statements to acquire WRITE locks for this dialect.
`boolean`	`isCurrentTimestampSelectStringCallable()` Should the value returned by `Dialect.getCurrentTimestampSelectString()` be treated as callable.
`char`	`openQuote()` The character specific to this dialect used to begin a quoted identifier.
`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`	`qualifyIndexName()` Do we need to qualify index names with the schema name?
`int`	`registerResultSetOutParameter(CallableStatement statement, int col)` Registers an OUT parameter which will be returning a `ResultSet`.
`protected void`	`registerVarcharTypes()`
`boolean`	`supportsCascadeDelete()`
`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`	`supportsIdentityColumns()` Does this dialect support identity column key generation?
`boolean`	`supportsIfExistsBeforeTableName()`
`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`	`supportsRowValueConstructorSyntax()` Is this dialect known to support what ANSI-SQL terms "row value constructor" syntax; sometimes called tuple syntax.
`boolean`	`supportsSubqueryOnMutatingTable()` Does this dialect support referencing the table being mutated in a subquery.
`boolean`	`supportsTemporaryTables()` Does this dialect support temporary tables?

Methods inherited from class org.hibernate.dialect.Dialect
appendIdentitySelectToInsert, appendLockHint, appendLockHint, applyLocksToSql, bindLimitParametersFirst, bindLimitParametersInReverseOrder, buildLimitHandler, buildSQLExceptionConverter, cast, cast, cast, convertToFirstRowValue, createCaseFragment, createOuterJoinFragment, doesReadCommittedCauseWritersToBlockReaders, doesRepeatableReadCauseReadersToBlockWriters, dropConstraints, dropTemporaryTableAfterUse, forceLimitUsage, forceLobAsLastValue, forUpdateOfColumns, generateTemporaryTableName, getAddPrimaryKeyConstraintString, getAddUniqueConstraintString, getCascadeConstraintsString, getCaseInsensitiveLike, getColumnAliasExtractor, getCreateMultisetTableString, getCreateSequenceString, getCreateSequenceString, getCreateSequenceStrings, getCreateSequenceStrings, getCreateTableString, getCreateTemporaryTablePostfix, getCrossJoinSeparator, getCurrentTimestampSQLFunctionName, getDefaultProperties, getDialect, getDialect, getDropSequenceString, getDropSequenceStrings, getDropTableString, getForUpdateNowaitString, getForUpdateNowaitString, getForUpdateString, getForUpdateString, getForUpdateString, getForUpdateString, getFunctions, getHibernateTypeName, getHibernateTypeName, getIdentityColumnString, getIdentityInsertString, getIdentitySelectString, getInExpressionCountLimit, getKeywords, getLimitString, getLobMergeStrategy, getLockingStrategy, getLowercaseFunction, getMaxAliasLength, getNativeIdentifierGeneratorClass, getNoColumnsInsertString, getNullColumnString, getQuerySequencesString, getSelectClauseNullString, getSelectSequenceNextValString, getSequenceNextValString, getSqlTypeDescriptorOverride, getTableTypeString, getTypeName, getTypeName, getViolatedConstraintNameExtracter, hasAlterTable, hasDataTypeInIdentityColumn, hasSelfReferentialForeignKeyBug, isLockTimeoutParameterized, quote, registerColumnType, registerColumnType, registerFunction, registerHibernateType, registerHibernateType, registerKeyword, remapSqlTypeDescriptor, replaceResultVariableInOrderByClauseWithPosition, requiresCastingOfParametersInSelectClause, supportsBindAsCallableArgument, supportsCaseInsensitiveLike, supportsCircularCascadeDeleteConstraints, supportsColumnCheck, supportsCommentOn, supportsExistsInSelect, supportsExpectedLobUsagePattern, supportsIfExistsAfterTableName, supportsInsertSelectIdentity, supportsLimitOffset, supportsNotNullUnique, supportsOuterJoinForUpdate, supportsParametersInInsertSelect, supportsPooledSequences, supportsResultSetPositionQueryMethodsOnForwardOnlyCursor, supportsRowValueConstructorSyntaxInInList, supportsSequences, supportsSubselectAsInPredicateLHS, supportsTableCheck, supportsTupleCounts, supportsTupleDistinctCounts, supportsUnboundedLobLocatorMaterialization, supportsUnionAll, supportsUnique, supportsUniqueConstraintInCreateAlterTable, supportsVariableLimit, toBooleanValueString, toString, transformSelectString, useFollowOnLocking, useInputStreamToInsertBlob, useMaxForLimit

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

- Constructor Detail
  - MySQLDialect
```
public MySQLDialect()
```
- Method Detail
  - registerVarcharTypes
```
protected void registerVarcharTypes()
```
  - 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.
  - qualifyIndexName
```
public boolean qualifyIndexName()
```
    Description copied from class: Dialect
    
    Do we need to qualify index names with the schema name?
    
    Overrides:
    
    qualifyIndexName in class Dialect
    
    Returns:
    boolean
  - 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.
  - 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
  - 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.
  - getAddForeignKeyConstraintString
```
public String getAddForeignKeyConstraintString(String constraintName,
                                      String[] foreignKey,
                                      String referencedTable,
                                      String[] primaryKey,
                                      boolean referencesPrimaryKey)
```
    Description copied from class: Dialect
    
    The syntax used to add a foreign key constraint to a table.
    
    Overrides:
    
    getAddForeignKeyConstraintString in class Dialect
    
    Parameters:
    constraintName - The FK constraint name.
    foreignKey - The names of the columns comprising the FK
    referencedTable - The table referenced by the FK
    primaryKey - The explicit columns in the referencedTable referenced by this FK.
    referencesPrimaryKey - if false, constraint should be explicit about which column names the constraint refers to
    
    Returns:
    the "add FK" fragment
  - 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.
  - getDropForeignKeyString
```
public String getDropForeignKeyString()
```
    Overrides:
    
    getDropForeignKeyString in class Dialect
  - 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
  - closeQuote
```
public char closeQuote()
```
    Description copied from class: Dialect
    
    The character specific to this dialect used to close a quoted identifier.
    
    Overrides:
    
    closeQuote in class Dialect
    
    Returns:
    The dialect's specific close quote character.
  - openQuote
```
public char openQuote()
```
    Description copied from class: Dialect
    
    The character specific to this dialect used to begin a quoted identifier.
    
    Overrides:
    
    openQuote in class Dialect
    
    Returns:
    The dialect's specific open quote character.
  - supportsIfExistsBeforeTableName
```
public boolean supportsIfExistsBeforeTableName()
```
    Overrides:
    
    supportsIfExistsBeforeTableName in class Dialect
  - getSelectGUIDString
```
public String getSelectGUIDString()
```
    Description copied from class: Dialect
    
    Get the command used to select a GUID from the underlying database.
    Optional operation.
    
    Overrides:
    
    getSelectGUIDString in class Dialect
    
    Returns:
    The appropriate command.
  - supportsCascadeDelete
```
public boolean supportsCascadeDelete()
```
    Overrides:
    
    supportsCascadeDelete in class Dialect
  - getTableComment
```
public String getTableComment(String comment)
```
    Overrides:
    
    getTableComment in class Dialect
  - getColumnComment
```
public String getColumnComment(String comment)
```
    Overrides:
    
    getColumnComment 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.
  - getDropTemporaryTableString
```
public String getDropTemporaryTableString()
```
    Description copied from class: Dialect
    
    Command used to drop a temporary table.
    
    Overrides:
    
    getDropTemporaryTableString in class Dialect
    
    Returns:
    The command used to drop a temporary table.
  - 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.
  - getCastTypeName
```
public String getCastTypeName(int code)
```
    Description copied from class: Dialect
    
    Get the name of the database type appropriate for casting operations (via the CAST() SQL function) for the given Types typecode.
    
    Overrides:
    
    getCastTypeName in class Dialect
    
    Parameters:
    code - The Types typecode
    
    Returns:
    The database type name
  - 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.
  - registerResultSetOutParameter
```
public int registerResultSetOutParameter(CallableStatement statement,
                                int col)
                                  throws SQLException
```
    Description copied from class: Dialect
    
    Registers an OUT parameter which will be returning a ResultSet. How this is accomplished varies greatly from DB to DB, hence its inclusion (along with Dialect.getResultSet(java.sql.CallableStatement)) here.
    
    Overrides:
    
    registerResultSetOutParameter in class Dialect
    
    Parameters:
    statement - The callable statement.
    col - The bind position at which to register the OUT param.
    
    Returns:
    The number of (contiguous) bind positions used.
    
    Throws:
    
    SQLException - Indicates problems registering the OUT 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.
  - supportsRowValueConstructorSyntax
```
public boolean supportsRowValueConstructorSyntax()
```
    Description copied from class: Dialect
    
    Is this dialect known to support what ANSI-SQL terms "row value constructor" syntax; sometimes called tuple syntax.
    Basically, does it support syntax like "... where (FIRST_NAME, LAST_NAME) = ('Steve', 'Ebersole') ...".
    
    Overrides:
    
    supportsRowValueConstructorSyntax in class Dialect
    
    Returns:
    True if this SQL dialect is known to support "row value constructor" syntax; false otherwise.
  - 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.
  - getWriteLockString
```
public String getWriteLockString(int timeout)
```
    Description copied from class: Dialect
    
    Get the string to append to SELECT statements to acquire WRITE locks for this dialect. Location of the of the returned string is treated the same as getForUpdateString.
    
    Overrides:
    
    getWriteLockString in class Dialect
    
    Parameters:
    timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
    
    Returns:
    The appropriate LOCK clause string.
  - getReadLockString
```
public String getReadLockString(int timeout)
```
    Description copied from class: Dialect
    
    Get the string to append to SELECT statements to acquire WRITE locks for this dialect. Location of the of the returned string is treated the same as getForUpdateString.
    
    Overrides:
    
    getReadLockString in class Dialect
    
    Parameters:
    timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
    
    Returns:
    The appropriate LOCK clause string.
  - 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.
  - areStringComparisonsCaseInsensitive
```
public boolean areStringComparisonsCaseInsensitive()
```
    Description copied from class: Dialect
    
    Are string comparisons implicitly case insensitive.
    In other words, does [where 'XYZ' = 'xyz'] resolve to true?
    
    Overrides:
    
    areStringComparisonsCaseInsensitive in class Dialect
    
    Returns:
    True if comparisons are case insensitive.
  - 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.
  - supportsSubqueryOnMutatingTable
```
public boolean supportsSubqueryOnMutatingTable()
```
    Description copied from class: Dialect
    Does this dialect support referencing the table being mutated in a subquery. The "table being mutated" is the table referenced in an UPDATE or a DELETE query. And so can that table then be referenced in a subquery of said UPDATE/DELETE query.
    For example, would the following two syntaxes be supported:
    - delete from TABLE_A where ID not in ( select ID from TABLE_A )
    - update TABLE_A set NON_ID = 'something' where ID in ( select ID from TABLE_A)
    Overrides:
    
    supportsSubqueryOnMutatingTable in class Dialect
    
    Returns:
    True if this dialect allows references the mutating table from a subquery.
  - 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.
  - 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 a 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
  - getNotExpression
```
public String getNotExpression(String expression)
```
    Overrides:
    
    getNotExpression in class Dialect

Class MySQLDialect

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

MySQLDialect

Method Detail

registerVarcharTypes

getAddColumnString

qualifyIndexName

supportsIdentityColumns

getIdentitySelectString

getIdentityColumnString

getAddForeignKeyConstraintString

supportsLimit

getDropForeignKeyString

getLimitString

closeQuote

openQuote

supportsIfExistsBeforeTableName

getSelectGUIDString

supportsCascadeDelete

getTableComment

getColumnComment

supportsTemporaryTables

getCreateTemporaryTableString

getDropTemporaryTableString

performTemporaryTableDDLInIsolation

getCastTypeName

supportsCurrentTimestampSelection

isCurrentTimestampSelectStringCallable

getCurrentTimestampSelectString

registerResultSetOutParameter

getResultSet

supportsRowValueConstructorSyntax

getForUpdateString

getWriteLockString

getReadLockString

supportsEmptyInList

areStringComparisonsCaseInsensitive

supportsLobValueChangePropogation

supportsSubqueryOnMutatingTable

supportsLockTimeouts

buildSQLExceptionConversionDelegate

getNotExpression