Class Dialect

    • Field Detail

      • CLOSED_QUOTE

        public static final String CLOSED_QUOTE
        Characters used as closing for quoting SQL identifiers
        See Also:
        Constant Field Values
      • LOG_BASE2OF10

        protected static final double LOG_BASE2OF10
      • LEGACY_LOB_MERGE_STRATEGY

        protected static final LobMergeStrategy LEGACY_LOB_MERGE_STRATEGY
        A LobMergeStrategy representing the legacy behavior of Hibernate. LOBs are not processed by merge.
      • STREAM_XFER_LOB_MERGE_STRATEGY

        protected static final LobMergeStrategy STREAM_XFER_LOB_MERGE_STRATEGY
        A LobMergeStrategy based on transferring contents using streams.
      • NEW_LOCATOR_LOB_MERGE_STRATEGY

        protected static final LobMergeStrategy NEW_LOCATOR_LOB_MERGE_STRATEGY
        A LobMergeStrategy based on creating a new LOB locator.
    • Method Detail

      • checkVersion

        protected void checkVersion()
      • isLob

        protected boolean isLob​(int sqlTypeCode)
      • castType

        protected String castType​(int sqlTypeCode)
        The SQL type to use in cast( ... as ... ) expressions when casting to the target type represented by the given JDBC type code.
        Parameters:
        sqlTypeCode - The JDBC type code representing the target type
        Returns:
        The SQL type to use in cast()
      • registerDefaultKeywords

        protected void registerDefaultKeywords()
        Register the reserved words of ANSI-standard SQL as keywords.
        See Also:
        AnsiSqlKeywords
      • getVersion

        public DatabaseVersion getVersion()
        Get the version of the SQL dialect that is the target of this instance.
      • getMinimumSupportedVersion

        protected DatabaseVersion getMinimumSupportedVersion()
        Get the version of the SQL dialect that is the minimum supported by this implementation.
      • resolveSqlTypeCode

        protected Integer resolveSqlTypeCode​(String columnTypeName,
                                             TypeConfiguration typeConfiguration)
        Resolves the SqlTypes type code for the given column type name as reported by the database, or null if it can't be resolved.
      • resolveSqlTypeCode

        protected Integer resolveSqlTypeCode​(String typeName,
                                             String baseTypeName,
                                             TypeConfiguration typeConfiguration)
        Resolves the SqlTypes type code for the given column type name as reported by the database and the base type name (i.e. without precision, length and scale), or null if it can't be resolved.
      • resolveSqlTypeDescriptor

        public JdbcType resolveSqlTypeDescriptor​(String columnTypeName,
                                                 int jdbcTypeCode,
                                                 int precision,
                                                 int scale,
                                                 JdbcTypeRegistry jdbcTypeRegistry)
        Assigns an appropriate JdbcType to a column of a JDBC result set based on the column type name, JDBC type code, precision, and scale.
        Parameters:
        columnTypeName - the column type name
        jdbcTypeCode - the type code
        precision - the precision or 0
        scale - the scale or 0
        Returns:
        an appropriate instance of JdbcType
      • resolveSqlTypeLength

        public int resolveSqlTypeLength​(String columnTypeName,
                                        int jdbcTypeCode,
                                        int precision,
                                        int scale,
                                        int displaySize)
        Determine the length/precision of a column based on information in the JDBC ResultSetMetaData. Note that what JDBC reports as a "precision" might actually be the column length.
        Parameters:
        columnTypeName - the name of the column type
        jdbcTypeCode - the JDBC type code of the column type
        precision - the (numeric) precision or (character) length of the column
        scale - the scale of a numeric column
        displaySize - the display size of the column
        Returns:
        the precision or length of the column
      • getEnumTypeDeclaration

        public String getEnumTypeDeclaration​(String name,
                                             String[] values)
        If this database has a special MySQL-style enum column type, return the type declaration for the given enumeration of values.

        If the database has no such type, return null.

        Parameters:
        values - the enumerated values of the type
        Returns:
        the DDL column type declaration
      • getEnumTypeDeclaration

        public String getEnumTypeDeclaration​(Class<? extends Enum<?>> enumType)
      • getCreateEnumTypeCommand

        public String[] getCreateEnumTypeCommand​(String name,
                                                 String[] values)
      • getCreateEnumTypeCommand

        public String[] getCreateEnumTypeCommand​(Class<? extends Enum<?>> enumType)
      • getDropEnumTypeCommand

        public String[] getDropEnumTypeCommand​(String name)
      • getDropEnumTypeCommand

        public String[] getDropEnumTypeCommand​(Class<? extends Enum<?>> enumType)
      • getCheckCondition

        public String getCheckCondition​(String columnName,
                                        String[] values)
        Render a SQL check condition for a column that represents an enumerated value by its string representation or a given list of values (with NULL value allowed).
        Returns:
        a SQL expression that will occur in a check constraint
      • getCheckCondition

        public String getCheckCondition​(String columnName,
                                        Class<? extends Enum<?>> enumType)
      • getCheckCondition

        public String getCheckCondition​(String columnName,
                                        long min,
                                        long max)
        Render a SQL check condition for a column that represents an enumerated value. by its ordinal representation.
        Returns:
        a SQL expression that will occur in a check constraint
      • getCheckCondition

        public String getCheckCondition​(String columnName,
                                        Long[] values)
        Render a SQL check condition for a column that represents an enumerated value by its ordinal representation or a given list of values.
        Returns:
        a SQL expression that will occur in a check constraint
      • ordinal

        public int ordinal()
        Description copied from interface: FunctionContributor
        Determines order in which the contributions will be applied (lowest ordinal first).

        The range 0-500 is reserved for Hibernate, range 500-1000 for libraries and 1000-Integer.MAX_VALUE for user-defined FunctionContributors.

        Contributions from higher precedence contributors (higher numbers) effectively override contributions from lower precedence. E.g. if a contributor with precedence 1000 contributes a function named "max", that will override Hibernate's standard function of that name.

        Specified by:
        ordinal in interface FunctionContributor
        Returns:
        the ordinal for this FunctionContributor
      • initializeFunctionRegistry

        public void initializeFunctionRegistry​(FunctionContributions functionContributions)
        Initialize the given registry with any dialect-specific functions.

        Support for certain SQL functions is required, and if the database does not support a required function, then the dialect must define a way to emulate it.

        These required functions include the functions defined by the JPA query language specification:

        • avg(arg) - aggregate function
        • count([distinct ]arg) - aggregate function
        • max(arg) - aggregate function
        • min(arg) - aggregate function
        • sum(arg) - aggregate function
        • coalesce(arg0, arg1, ...)
        • nullif(arg0, arg1)
        • lower(arg)
        • upper(arg)
        • length(arg)
        • concat(arg0, arg1, ...)
        • locate(pattern, string[, start])
        • substring(string, start[, length])
        • trim([[spec ][character ]from] string)
        • abs(arg)
        • mod(arg0, arg1)
        • sqrt(arg)
        • current date
        • current time
        • current timestamp
        Along with an additional set of functions defined by ANSI SQL:
        • any(arg) - aggregate function
        • every(arg) - aggregate function
        • var_samp(arg) - aggregate function
        • var_pop(arg) - aggregate function
        • stddev_samp(arg) - aggregate function
        • stddev_pop(arg) - aggregate function
        • cast(arg as Type)
        • extract(field from arg)
        • ln(arg)
        • exp(arg)
        • power(arg0, arg1)
        • floor(arg)
        • ceiling(arg)
        • position(pattern in string)
        • substring(string from start[ for length])
        • overlay(string placing replacement from start[ for length])
        And the following functions for working with java.time types:
        • local date
        • local time
        • local datetime
        • offset datetime
        • instant
        And a number of additional "standard" functions:
        • left(string, length)
        • right(string, length)
        • replace(string, pattern, replacement)
        • pad(string with length spec[ character])
        • repeat(string, times)
        • pi
        • log10(arg)
        • log(base, arg)
        • sign(arg)
        • sin(arg)
        • cos(arg)
        • tan(arg)
        • asin(arg)
        • acos(arg)
        • atan(arg)
        • atan2(arg0, arg1)
        • round(arg0[, arg1])
        • truncate(arg0[, arg1])
        • sinh(arg)
        • tanh(arg)
        • cosh(arg)
        • least(arg0, arg1, ...)
        • greatest(arg0, arg1, ...)
        • degrees(arg)
        • radians(arg)
        • bitand(arg1, arg1)
        • bitor(arg1, arg1)
        • bitxor(arg1, arg1)
        • format(datetime as pattern)
        • collate(string as collation)
        • str(arg) - synonym of cast(a as String)
        • ifnull(arg0, arg1) - synonym of coalesce(a, b)
        Finally, the following functions are defined as abbreviations for extract(), and desugared by the parser:
        • second(arg) - synonym of extract(second from a)
        • minute(arg) - synonym of extract(minute from a)
        • hour(arg) - synonym of extract(hour from a)
        • day(arg) - synonym of extract(day from a)
        • month(arg) - synonym of extract(month from a)
        • year(arg) - synonym of extract(year from a)
        Note that according to this definition, the second() function returns a floating point value, contrary to the integer type returned by the native function with this name on many databases. Thus, we don't just naively map these HQL functions to the native SQL functions with the same names.
      • currentDate

        public String currentDate()
        Translation of the HQL/JPQL current_date function, which maps to the Java type Date, and of the HQL local_date function which maps to the Java type LocalDate.
      • currentTime

        public String currentTime()
        Translation of the HQL/JPQL current_time function, which maps to the Java type Time which is a time with no time zone. This contradicts ANSI SQL where current_time has the type TIME WITH TIME ZONE.

        It is recommended to override this in dialects for databases which support localtime or time at local.

      • currentTimestamp

        public String currentTimestamp()
        Translation of the HQL/JPQL current_timestamp function, which maps to the Java type Timestamp which is a datetime with no time zone. This contradicts ANSI SQL where current_timestamp has the type TIMESTAMP WITH TIME ZONE.

        It is recommended to override this in dialects for databases which support localtimestamp or timestamp at local.

      • currentLocalTime

        public String currentLocalTime()
        Translation of the HQL local_time function, which maps to the Java type LocalTime which is a time with no time zone. It should usually be the same SQL function as for currentTime().

        It is recommended to override this in dialects for databases which support localtime or current_time at local.

      • currentLocalTimestamp

        public String currentLocalTimestamp()
        Translation of the HQL local_datetime function, which maps to the Java type LocalDateTime which is a datetime with no time zone. It should usually be the same SQL function as for currentTimestamp().

        It is recommended to override this in dialects for databases which support localtimestamp or current_timestamp at local.

      • currentTimestampWithTimeZone

        public String currentTimestampWithTimeZone()
        Translation of the HQL offset_datetime function, which maps to the Java type OffsetDateTime which is a datetime with a time zone. This in principle correctly maps to the ANSI SQL current_timestamp which has the type TIMESTAMP WITH TIME ZONE.
      • castPattern

        public String castPattern​(CastType from,
                                  CastType to)
        Obtain a pattern for the SQL equivalent to a cast() function call. The resulting pattern must contain ?1 and ?2 placeholders for the arguments.
        Parameters:
        from - a CastType indicating the type of the value argument
        to - a CastType indicating the type the value argument is cast to
      • trimPattern

        @Deprecated(forRemoval=true)
        public String trimPattern​(TrimSpec specification,
                                  char character)
        Deprecated, for removal: This API element is subject to removal in a future version.
        Obtain a pattern for the SQL equivalent to a trim() function call. The resulting pattern must contain a ?1 placeholder for the argument of type String.
        Parameters:
        specification - leading or trailing
        character - the character to trim
      • trimPattern

        public String trimPattern​(TrimSpec specification,
                                  boolean isWhitespace)
        Obtain a pattern for the SQL equivalent to a trim() function call. The resulting pattern must contain a ?1 placeholder for the argument of type String and a ?2 placeholder for the trim character if isWhitespace was false.
        Parameters:
        specification - leading, trailing or both
        isWhitespace - true if the trim character is a whitespace and can be omitted, false if it must be explicit and a ?2 placeholder should be included in the pattern
      • supportsFractionalTimestampArithmetic

        public boolean supportsFractionalTimestampArithmetic()
        Whether the database supports adding a fractional interval to a timestamp, for example timestamp + 0.5 second.
      • timestampdiffPattern

        public String timestampdiffPattern​(TemporalUnit unit,
                                           TemporalType fromTemporalType,
                                           TemporalType toTemporalType)
        Obtain a pattern for the SQL equivalent to a timestampdiff() function call. The resulting pattern must contain ?1, ?2, and ?3 placeholders for the arguments.
        Parameters:
        unit - the first argument
        fromTemporalType - true if the first argument is a timestamp, false if a date
        toTemporalType - true if the second argument is
      • timestampaddPattern

        public String timestampaddPattern​(TemporalUnit unit,
                                          TemporalType temporalType,
                                          IntervalType intervalType)
        Obtain a pattern for the SQL equivalent to a timestampadd() function call. The resulting pattern must contain ?1, ?2, and ?3 placeholders for the arguments.
        Parameters:
        unit - The unit to add to the temporal
        temporalType - The type of the temporal
        intervalType - The type of interval to add or null if it's not a native interval
      • equivalentTypes

        public boolean equivalentTypes​(int typeCode1,
                                       int typeCode2)
        Do the given JDBC type codes, as defined in Types represent essentially the same type in this dialect of SQL?

        The default implementation treats NUMERIC and DECIMAL as the same type, and FLOAT, REAL, and DOUBLE as essentially the same type, since the ANSI SQL specification fails to meaningfully distinguish them.

        The default implementation also treats VARCHAR, NVARCHAR, LONGVARCHAR, and LONGNVARCHAR as the same type, and BINARY and LONGVARBINARY as the same type, since Hibernate doesn't really differentiate these types.

        Parameters:
        typeCode1 - the first column type info
        typeCode2 - the second column type info
        Returns:
        true if the two type codes are equivalent
      • getDefaultProperties

        public Properties getDefaultProperties()
        Retrieve a set of default Hibernate properties for this database.

        An implementation may set configuration properties from initDefaultProperties(), though it is discouraged. the

        Returns:
        the Hibernate configuration properties
        See Also:
        initDefaultProperties()
      • getDefaultStatementBatchSize

        public int getDefaultStatementBatchSize()
        The default value to use for the configuration property "hibernate.jdbc.batch_size".
      • contributeTypes

        public void contributeTypes​(TypeContributions typeContributions,
                                    ServiceRegistry serviceRegistry)
        A callback which allows the Dialect to contribute types.
        Parameters:
        typeContributions - Callback to contribute the types
        serviceRegistry - The service registry
      • getNativeIdentifierGeneratorStrategy

        public String getNativeIdentifierGeneratorStrategy()
        The name identifying the "native" id generation strategy for this dialect.

        This is the name of the id generation strategy which should be used when "native" is specified in hbm.xml.

        Returns:
        The name identifying the native generator strategy.
      • getQuerySequencesString

        public String getQuerySequencesString()
        Get the select command used retrieve the names of all sequences.
        Returns:
        The select command; or null if sequences are not supported.
      • getSelectGUIDString

        public String getSelectGUIDString()
        Get the command used to select a GUID from the database.

        Optional operation.

        Returns:
        The appropriate command.
      • supportsTemporaryTables

        public boolean supportsTemporaryTables()
        Does this database have some sort of support for temporary tables?
        Returns:
        true by default, since most do
      • supportsTemporaryTablePrimaryKey

        public boolean supportsTemporaryTablePrimaryKey()
        Does this database support primary keys for temporary tables?
        Returns:
        true by default, since most do
      • supportsLockTimeouts

        public boolean supportsLockTimeouts()
        Does this dialect support specifying timeouts when requesting locks.
        Returns:
        True is this dialect supports specifying lock timeouts.
      • isLockTimeoutParameterized

        @Deprecated(since="6",
                    forRemoval=true)
        public boolean isLockTimeoutParameterized()
        Deprecated, for removal: This API element is subject to removal in a future version.
        This is never called, and since at least Hibernate 5 has just returned false in every dialect. It will be removed.
        If this dialect supports specifying lock timeouts, are those timeouts rendered into the SQL string as parameters? The implication is that Hibernate will need to bind the timeout value as a parameter in the PreparedStatement. If true, the parameter position is always handled as the last parameter; if the dialect specifies the lock timeout elsewhere in the SQL statement then the timeout value should be directly rendered into the statement and this method should return false.
        Returns:
        True if the lock timeout is rendered into the SQL string as a parameter; false otherwise.
      • getLockingStrategy

        public LockingStrategy getLockingStrategy​(Lockable lockable,
                                                  LockMode lockMode)
        A LockingStrategy which is able to acquire a database-level lock with the specified level.
        Parameters:
        lockable - The persister for the entity to be locked.
        lockMode - The type of lock to be acquired.
        Returns:
        The appropriate locking strategy.
        Since:
        3.2
      • getForUpdateString

        public String getForUpdateString​(LockOptions lockOptions)
        Given a set of LockOptions (lock level, timeout), determine the appropriate for update fragment to use to obtain the lock.
        Parameters:
        lockOptions - contains the lock mode to apply.
        Returns:
        The appropriate for update fragment.
      • getForUpdateString

        public String getForUpdateString​(LockMode lockMode)
        Given a LockMode, determine the appropriate for update fragment to use to obtain the lock.
        Parameters:
        lockMode - The lock mode to apply.
        Returns:
        The appropriate for update fragment.
      • getForUpdateString

        public String getForUpdateString()
        Get the string to append to SELECT statements to acquire pessimistic UPGRADE locks for this dialect.
        Returns:
        The appropriate FOR UPDATE clause string.
      • getWriteLockString

        public String getWriteLockString​(int timeout)
        Get the string to append to SELECT statements to acquire pessimistic WRITE locks for this dialect.

        Location of the returned string is treated the same as getForUpdateString().

        Parameters:
        timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
        Returns:
        The appropriate LOCK clause string.
      • getWriteLockString

        public String getWriteLockString​(String aliases,
                                         int timeout)
        Get the string to append to SELECT statements to acquire WRITE locks for this dialect, given the aliases of the columns to be write locked.

        Location of the returned string is treated the same as getForUpdateString().

        Parameters:
        aliases - The columns to be read locked.
        timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
        Returns:
        The appropriate LOCK clause string.
      • getReadLockString

        public String getReadLockString​(int timeout)
        Get the string to append to SELECT statements to acquire READ locks for this dialect.

        Location of the returned string is treated the same as getForUpdateString().

        Parameters:
        timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
        Returns:
        The appropriate LOCK clause string.
      • getReadLockString

        public String getReadLockString​(String aliases,
                                        int timeout)
        Get the string to append to SELECT statements to acquire READ locks for this dialect, given the aliases of the columns to be read locked.

        Location of the returned string is treated the same as getForUpdateString().

        Parameters:
        aliases - The columns to be read locked.
        timeout - in milliseconds, -1 for indefinite wait and 0 for no wait.
        Returns:
        The appropriate LOCK clause string.
      • supportsOuterJoinForUpdate

        public boolean supportsOuterJoinForUpdate()
        Does this dialect support FOR UPDATE in conjunction with outer-joined rows?
        Returns:
        True if outer-joined rows can be locked via FOR UPDATE.
      • getForUpdateString

        public String getForUpdateString​(String aliases)
        Get the FOR UPDATE OF column_list fragment appropriate for this dialect, given the aliases of the columns to be write locked.
        Parameters:
        aliases - The columns to be write locked.
        Returns:
        The appropriate FOR UPDATE OF column_list clause string.
      • getForUpdateString

        public String getForUpdateString​(String aliases,
                                         LockOptions lockOptions)
        Get the FOR UPDATE OF or FOR SHARE OF fragment appropriate for this dialect, given the aliases of the columns to be locked.
        Parameters:
        aliases - The columns to be locked.
        lockOptions - the lock options to apply
        Returns:
        The appropriate FOR UPDATE OF column_list clause string.
      • getForUpdateNowaitString

        public String getForUpdateNowaitString()
        Retrieves the FOR UPDATE NOWAIT syntax specific to this dialect.
        Returns:
        The appropriate FOR UPDATE NOWAIT clause string.
      • getForUpdateSkipLockedString

        public String getForUpdateSkipLockedString()
        Retrieves the FOR UPDATE SKIP LOCKED syntax specific to this dialect.
        Returns:
        The appropriate FOR UPDATE SKIP LOCKED clause string.
      • getForUpdateNowaitString

        public String getForUpdateNowaitString​(String aliases)
        Get the FOR UPDATE OF column_list NOWAIT fragment appropriate for this dialect, given the aliases of the columns to be write locked.
        Parameters:
        aliases - The columns to be write locked.
        Returns:
        The appropriate FOR UPDATE OF colunm_list NOWAIT clause string.
      • getForUpdateSkipLockedString

        public String getForUpdateSkipLockedString​(String aliases)
        Get the FOR UPDATE OF column_list SKIP LOCKED fragment appropriate for this dialect, given the aliases of the columns to be write locked.
        Parameters:
        aliases - The columns to be write locked.
        Returns:
        The appropriate FOR UPDATE colunm_list SKIP LOCKED clause string.
      • appendLockHint

        public String appendLockHint​(LockOptions lockOptions,
                                     String tableName)
        Some dialects support an alternative means to SELECT FOR UPDATE, whereby a "lock hint" is appended to the table name in the from clause.
        Parameters:
        lockOptions - The lock options to apply
        tableName - The name of the table to which to apply the lock hint.
        Returns:
        The table with any required lock hints.
      • applyLocksToSql

        public String applyLocksToSql​(String sql,
                                      LockOptions aliasedLockOptions,
                                      Map<String,​String[]> keyColumnNames)
        Modifies the given SQL, applying the appropriate updates for the specified lock modes and key columns.

        This allows emulation of SELECT FOR UPDATE for dialects which do not support the standard syntax.

        Parameters:
        sql - the SQL string to modify
        aliasedLockOptions - lock options indexed by aliased table names.
        keyColumnNames - a map of key columns indexed by aliased table names.
        Returns:
        the modified SQL string.
      • getTimeoutInSeconds

        protected int getTimeoutInSeconds​(int millis)
      • getCreateTableString

        public String getCreateTableString()
        The command used to create a table, usually create table.
        Returns:
        The command used to create a table.
      • getTableTypeString

        public String getTableTypeString()
        An arbitrary fragment appended to the end of the create table statement.
        API Note:
        An example is the MySQL engine option specifying a storage engine.
      • supportsIfExistsBeforeTableName

        public boolean supportsIfExistsBeforeTableName()
        For dropping a table, can the phrase if exists be applied before the table name?
        Returns:
        true if if exists can be applied before the table name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsAfterTableName() should return true.
      • supportsIfExistsAfterTableName

        public boolean supportsIfExistsAfterTableName()
        For dropping a table, can the phrase if exists be applied after the table name?
        Returns:
        true if if exists can be applied after the table name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsBeforeTableName() should return true.
      • getDropTableString

        public String getDropTableString​(String tableName)
        The command used to drop a table with the given name, usually drop table tab_name.
        Parameters:
        tableName - The name of the table to drop
        Returns:
        The drop table statement as a string
      • getCreateIndexString

        public String getCreateIndexString​(boolean unique)
        The command used to create an index, usually create index or create unique index.
        Parameters:
        unique - true if the index is a unique index
        Returns:
        The command used to create an index.
      • getCreateIndexTail

        public String getCreateIndexTail​(boolean unique,
                                         List<Column> columns)
        A string to be appended to the end of the create index command, usually to specify that null values are to be considered distinct.
      • qualifyIndexName

        public boolean qualifyIndexName()
        Do we need to qualify index names with the schema name?
        Returns:
        true if we do
      • getCreateMultisetTableString

        public String getCreateMultisetTableString()
        Slight variation on getCreateTableString(). Here, we have the command used to create a table when there is no primary key and duplicate rows are expected.
        Returns:
        The command used to create a multiset table.
        API Note:
        Most databases do not have this distinction; this method was originally added for Teradata which does.
      • hasAlterTable

        public boolean hasAlterTable()
        Does this dialect support the ALTER TABLE syntax?
        Returns:
        True if we support altering existing tables; false otherwise.
      • getAlterTableString

        public String getAlterTableString​(String tableName)
        The command used to alter a table with the given name, usually alter table tab_name or alter table tab_name if exists.

        We prefer the if exists form if supported.

        Parameters:
        tableName - The name of the table to alter
        Returns:
        The command used to alter a table.
        Since:
        5.2.11
      • supportsIfExistsAfterAlterTable

        public boolean supportsIfExistsAfterAlterTable()
        For an alter table, can the phrase if exists be applied?
        Returns:
        true if if exists can be applied after alter table
        Since:
        5.2.11
      • getAddColumnString

        public String getAddColumnString()
        The subcommand of the alter table command used to add a column to a table, usually add column or add.
        Returns:
        The add column fragment.
      • getAddColumnSuffixString

        public String getAddColumnSuffixString()
        The syntax for the suffix used to add a column to a table.
        Returns:
        The suffix of the add column fragment.
      • dropConstraints

        public boolean dropConstraints()
        Do we need to drop constraints before dropping tables in this dialect?
        Returns:
        True if constraints must be dropped prior to dropping the table; false otherwise.
      • getDropForeignKeyString

        public String getDropForeignKeyString()
        The subcommand of the alter table command used to drop a foreign key constraint, usually drop constraint.
      • getDropUniqueKeyString

        public String getDropUniqueKeyString()
        The subcommand of the alter table command used to drop a unique key constraint.
      • supportsIfExistsBeforeConstraintName

        public boolean supportsIfExistsBeforeConstraintName()
        For dropping a constraint with an alter table statement, can the phrase if exists be applied before the constraint name?
        Returns:
        true if if exists can be applied before the constraint name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsAfterConstraintName() should return true
      • supportsIfExistsAfterConstraintName

        public boolean supportsIfExistsAfterConstraintName()
        For dropping a constraint with an alter table, can the phrase if exists be applied after the constraint name?
        Returns:
        true if if exists can be applied after the constraint name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsBeforeConstraintName() should return true.
      • supportsAlterColumnType

        public boolean supportsAlterColumnType()
        Does this dialect support modifying the type of an existing column?
      • getAlterColumnTypeString

        public String getAlterColumnTypeString​(String columnName,
                                               String columnType,
                                               String columnDefinition)
        The fragment of an alter table command which modifies a column type, or null if column types cannot be modified. Often alter column col_name set data type col_type.
        Parameters:
        columnName - the name of the column
        columnType - the new type of the column
        columnDefinition - the full column definition
        Returns:
        a fragment to be appended to alter table
      • getAddForeignKeyConstraintString

        public String getAddForeignKeyConstraintString​(String constraintName,
                                                       String[] foreignKey,
                                                       String referencedTable,
                                                       String[] primaryKey,
                                                       boolean referencesPrimaryKey)
        The syntax used to add a foreign key constraint to a table, with the referenced key columns explicitly specified.
        Parameters:
        constraintName - The foreign key constraint name
        foreignKey - The names of the columns comprising the foreign key
        referencedTable - The table referenced by the foreign key
        primaryKey - The explicit columns in the referencedTable referenced by this foreign key.
        referencesPrimaryKey - if false, constraint should be explicit about which column names the constraint refers to
        Returns:
        the "add FK" fragment
      • getAddForeignKeyConstraintString

        public String getAddForeignKeyConstraintString​(String constraintName,
                                                       String foreignKeyDefinition)
        The syntax used to add a foreign key constraint to a table, given the definition of the foreign key as a string.
        Parameters:
        constraintName - The foreign key constraint name
        foreignKeyDefinition - The whole definition of the foreign key as a fragment
      • getAddPrimaryKeyConstraintString

        public String getAddPrimaryKeyConstraintString​(String constraintName)
        The syntax used to add a primary key constraint to a table.
        Parameters:
        constraintName - The name of the PK constraint.
        Returns:
        The "add PK" fragment
      • getCreateUserDefinedTypeKindString

        public String getCreateUserDefinedTypeKindString()
        The kind of user-defined type to create, or the empty string if this does not need to be specified. Included after create type type_name as, but before the list of members.
      • getCreateUserDefinedTypeExtensionsString

        public String getCreateUserDefinedTypeExtensionsString()
        An arbitrary extension to append to the end of the UDT create type command.
      • supportsIfExistsBeforeTypeName

        public boolean supportsIfExistsBeforeTypeName()
        For dropping a type, can the phrase if exists be applied before the type name?
        Returns:
        true if if exists can be applied before the type name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsAfterTypeName() should return true.
      • supportsIfExistsAfterTypeName

        public boolean supportsIfExistsAfterTypeName()
        For dropping a type, can the phrase if exists be applied after the type name?
        Returns:
        true if if exists can be applied after the type name
        API Note:
        Only one or the other (or neither) of this and supportsIfExistsBeforeTypeName() should return true.
      • registerResultSetOutParameter

        public int registerResultSetOutParameter​(CallableStatement statement,
                                                 int position)
                                          throws SQLException
        Registers a parameter capable of returning a ResultSet by position, either an OUT parameter, or a REF_CURSOR parameter as defined in Java 8.
        Parameters:
        statement - The callable statement.
        position - 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.
        API Note:
        Before Java 8, support for ResultSet-returning parameters was very uneven across database and drivers, leading to its inclusion as part of the Dialect contract.
      • registerResultSetOutParameter

        public int registerResultSetOutParameter​(CallableStatement statement,
                                                 String name)
                                          throws SQLException
        Registers a parameter capable of returning a ResultSet by name, either an OUT parameter, or a REF_CURSOR parameter as defined in Java 8.
        Parameters:
        statement - The callable statement.
        name - The parameter name (for drivers which support named parameters).
        Returns:
        The number of (contiguous) bind positions used.
        Throws:
        SQLException - Indicates problems registering the param.
        API Note:
        Before Java 8, support for ResultSet-returning parameters was very uneven across database and drivers, leading to its inclusion as part of the Dialect contract.
      • supportsCurrentTimestampSelection

        public boolean supportsCurrentTimestampSelection()
        Does this dialect support some way to retrieve the current timestamp value from the database?
        Returns:
        True if the current timestamp can be retrieved; false otherwise.
      • isCurrentTimestampSelectStringCallable

        public boolean isCurrentTimestampSelectStringCallable()
        Is the command returned by getCurrentTimestampSelectString() treated as callable?

        Typically, this indicates the use of the JDBC escape syntax.

        Returns:
        if the getCurrentTimestampSelectString() is treated as callable; false otherwise.
      • getCurrentTimestampSelectString

        public String getCurrentTimestampSelectString()
        The command used to retrieve the current timestamp from the database.
      • supportsStandardCurrentTimestampFunction

        public boolean supportsStandardCurrentTimestampFunction()
        Does this dialect have an ANSI SQL current_timestamp function?
      • getSelectClauseNullString

        public String getSelectClauseNullString​(int sqlType,
                                                TypeConfiguration typeConfiguration)
        Given a JDBC type code, return the expression for a literal null value of that type, to use in a select clause.

        The select query will be an element of a UNION or UNION ALL.

        Parameters:
        sqlType - The Types type code.
        typeConfiguration - The type configuration
        Returns:
        The appropriate select clause value fragment.
        Implementation Note:
        Some databases require an explicit type cast.
      • supportsUnionAll

        public boolean supportsUnionAll()
        Does this dialect support UNION ALL?
        Returns:
        True if UNION ALL is supported; false otherwise.
      • supportsUnionInSubquery

        public boolean supportsUnionInSubquery()
        Does this dialect support UNION in a subquery.
        Returns:
        True if UNION is supported in a subquery; false otherwise.
      • getNoColumnsInsertString

        @Deprecated(since="6")
        public String getNoColumnsInsertString()
        Deprecated.
        Override the method renderInsertIntoNoColumns() on the translator returned by this dialect.
        The fragment used to insert a row without specifying any column values, usually just (), but sometimes default values.
        Returns:
        The appropriate empty values clause.
        Implementation Note:
        On the other hand, this is simply not possible on some databases!
      • supportsNoColumnsInsert

        public boolean supportsNoColumnsInsert()
        Is the INSERT statement is allowed to contain no columns?
        Returns:
        if this dialect supports no-column INSERT.
      • getLowercaseFunction

        public String getLowercaseFunction()
        The name of the SQL function that transforms a string to lowercase, almost always lower.
        Returns:
        The dialect-specific lowercase function.
      • getCaseInsensitiveLike

        public String getCaseInsensitiveLike()
        The name of the SQL operator that performs case-insensitive LIKE comparisons.
        Returns:
        The dialect-specific case-insensitive like operator.
      • supportsCaseInsensitiveLike

        public boolean supportsCaseInsensitiveLike()
        Does this dialect support case-insensitive LIKE comparisons?
        Returns:
        true if the database supports case-insensitive like comparisons, false otherwise. The default is false.
      • supportsTruncateWithCast

        public boolean supportsTruncateWithCast()
        Does this dialect support truncation of values to a specified length via a cast?
        Returns:
        true if the database supports truncation via a cast, false otherwise. The default is true.
      • supportsIsTrue

        public boolean supportsIsTrue()
        Does this dialect support the is true and is false operators?
        Returns:
        true if the database supports is true and is false, or false if it does not. The default is is false.
      • transformSelectString

        public String transformSelectString​(String select)
        Meant as a means for end users to affect the select strings being sent to the database and perhaps manipulate them in some fashion.
        Parameters:
        select - The select command
        Returns:
        The mutated select command, or the same as was passed in.
      • getMaxAliasLength

        public int getMaxAliasLength()
        What is the maximum length Hibernate can use for generated aliases?
        Returns:
        The maximum length.
        Implementation Note:
        The maximum here should account for the fact that Hibernate often needs to append "uniqueing" information to the end of generated aliases. That "uniqueing" information will be added to the end of an identifier generated to the length specified here; so be sure to leave some room (generally speaking 5 positions will suffice).
      • getMaxIdentifierLength

        public int getMaxIdentifierLength()
        What is the maximum identifier length supported by this dialect?
        Returns:
        The maximum length.
      • toBooleanValueString

        public String toBooleanValueString​(boolean bool)
        The SQL literal expression representing the given boolean value.
        Parameters:
        bool - The boolean value
        Returns:
        The appropriate SQL literal.
      • appendBooleanValueString

        public void appendBooleanValueString​(SqlAppender appender,
                                             boolean bool)
        Append the SQL literal expression representing the given boolean value to the given SqlAppender.
        Parameters:
        bool - The boolean value
        appender - The SqlAppender to append the literal expression to
      • registerKeyword

        protected void registerKeyword​(String word)
        Register a keyword.
        Parameters:
        word - a reserved word in this SQL dialect
      • getKeywords

        public Set<String> getKeywords()
        The keywords of this SQL dialect.
      • openQuote

        public char openQuote()
        The character specific to this dialect used to begin a quoted identifier.
        Returns:
        The dialect-specific open quote character.
      • closeQuote

        public char closeQuote()
        The character specific to this dialect used to close a quoted identifier.
        Returns:
        The dialect-specific close quote character.
      • toQuotedIdentifier

        public String toQuotedIdentifier​(String name)
        Apply dialect-specific quoting.
        Parameters:
        name - The value to be quoted.
        Returns:
        The quoted value.
        See Also:
        openQuote(), closeQuote()
      • quote

        public String quote​(String name)
        Apply dialect-specific quoting if the given name is quoted using backticks.

        By default, the incoming name is checked to see if its first character is a backtick (`). If it is, the dialect specific quoting is applied.

        Parameters:
        name - The value to be quoted.
        Returns:
        The quoted (or unmodified, if not starting with backtick) value.
        See Also:
        openQuote(), closeQuote()
      • getSupportedTemporaryTableKind

        public TemporaryTableKind getSupportedTemporaryTableKind()
        The kind of temporary tables that are supported on this database.
      • getTemporaryTableCreateOptions

        public String getTemporaryTableCreateOptions()
        An arbitrary SQL fragment appended to the end of the statement to create a temporary table, specifying dialect-specific options, or null if there are no options to specify.
      • getTemporaryTableCreateCommand

        public String getTemporaryTableCreateCommand()
        The command to create a temporary table.
      • getTemporaryTableDropCommand

        public String getTemporaryTableDropCommand()
        The command to drop a temporary table.
      • getTemporaryTableTruncateCommand

        public String getTemporaryTableTruncateCommand()
        The command to truncate a temporary table.
      • getCreateTemporaryTableColumnAnnotation

        public String getCreateTemporaryTableColumnAnnotation​(int sqlTypeCode)
        Annotation to be appended to the end of each COLUMN clause for temporary tables.
        Parameters:
        sqlTypeCode - The SQL type code
        Returns:
        The annotation to be appended, for example, COLLATE DATABASE_DEFAULT in SQL Server
      • getTemporaryTableAfterUseAction

        public AfterUseAction getTemporaryTableAfterUseAction()
        The action to take after finishing use of a temporary table.
      • getTemporaryTableBeforeUseAction

        public BeforeUseAction getTemporaryTableBeforeUseAction()
        The action to take before beginning use of a temporary table.
      • canCreateCatalog

        public boolean canCreateCatalog()
        Does this dialect support creating and dropping catalogs?
        Returns:
        True if the dialect supports catalog creation; false otherwise.
      • getCreateCatalogCommand

        public String[] getCreateCatalogCommand​(String catalogName)
        Get the SQL command used to create the named catalog.
        Parameters:
        catalogName - The name of the catalog to be created.
        Returns:
        The creation commands
      • getDropCatalogCommand

        public String[] getDropCatalogCommand​(String catalogName)
        Get the SQL command used to drop the named catalog.
        Parameters:
        catalogName - The name of the catalog to be dropped.
        Returns:
        The drop commands
      • canCreateSchema

        public boolean canCreateSchema()
        Does this dialect support creating and dropping schema?
        Returns:
        True if the dialect supports schema creation; false otherwise.
      • getCreateSchemaCommand

        public String[] getCreateSchemaCommand​(String schemaName)
        Get the SQL command used to create the named schema.
        Parameters:
        schemaName - The name of the schema to be created.
        Returns:
        The creation commands
      • getDropSchemaCommand

        public String[] getDropSchemaCommand​(String schemaName)
        Get the SQL command used to drop the named schema.
        Parameters:
        schemaName - The name of the schema to be dropped.
        Returns:
        The drop commands
      • getCurrentSchemaCommand

        public String getCurrentSchemaCommand()
        Get the SQL command used to retrieve the current schema name.

        Works in conjunction with getSchemaNameResolver(), unless the resulting SchemaNameResolver does not need this information. For example, a custom implementation might make use of the Java 1.7 Connection.getSchema() method.

        Returns:
        The current schema retrieval SQL
      • hasSelfReferentialForeignKeyBug

        public boolean hasSelfReferentialForeignKeyBug()
        Does the database/driver have bug in deleting rows that refer to other rows being deleted in the same query?
        Returns:
        true if the database/driver has this bug
        Implementation Note:
        The main culprit is MySQL.
      • getNullColumnString

        public String getNullColumnString()
        The keyword used to specify a nullable column, usually "", but sometimes " null".
      • getNullColumnString

        public String getNullColumnString​(String columnType)
        The keyword used to specify a nullable column of the given SQL type.
        Implementation Note:
        The culprit is timestamp columns on MySQL.
      • quoteCollation

        public String quoteCollation​(String collation)
        Quote the given collation name if necessary.
      • supportsCommentOn

        public boolean supportsCommentOn()
        Does this dialect support commenting on tables and columns?
        Returns:
        true if commenting is supported
      • getTableComment

        public String getTableComment​(String comment)
        Get the comment into a form supported for table definition.
        Parameters:
        comment - The comment to apply
        Returns:
        The comment fragment
      • getUserDefinedTypeComment

        public String getUserDefinedTypeComment​(String comment)
        Get the comment into a form supported for UDT definition.
        Parameters:
        comment - The comment to apply
        Returns:
        The comment fragment
      • getColumnComment

        public String getColumnComment​(String comment)
        Get the comment into a form supported for column definition.
        Parameters:
        comment - The comment to apply
        Returns:
        The comment fragment
      • supportsColumnCheck

        public boolean supportsColumnCheck()
        Does this dialect support column-level check constraints?
        Returns:
        True if column-level check constraints are supported; false otherwise.
      • supportsTableCheck

        public boolean supportsTableCheck()
        Does this dialect support table-level check constraints?
        Returns:
        True if table-level check constraints are supported; false otherwise.
      • supportsCascadeDelete

        public boolean supportsCascadeDelete()
        Does this dialect support on delete actions in foreign key definitions?
        Returns:
        true if the dialect does support the on delete clause.
      • getCascadeConstraintsString

        public String getCascadeConstraintsString()
        The keyword that specifies that a drop table operation should be cascaded to its constraints, typically " cascade" where the leading space is required, or the empty string if there is no such keyword in this dialect.
        Returns:
        The cascade drop keyword, if any, with a leading space
      • supportsParametersInInsertSelect

        @Deprecated(since="6",
                    forRemoval=true)
        public boolean supportsParametersInInsertSelect()
        Deprecated, for removal: This API element is subject to removal in a future version.
        This seems to be supported on all platforms, and we don't call this except in test suite
        Does this dialect support parameters within the SELECT clause of INSERT ... SELECT ... statements?
        Returns:
        True if this is supported; false otherwise.
        Since:
        3.2
      • supportsOrdinalSelectItemReference

        public boolean supportsOrdinalSelectItemReference()
        Does this dialect support references to result variables (i.e, select items) by column positions (1-origin) as defined by the select clause?
        Returns:
        true if result variable references by column positions are supported; false otherwise.
        Since:
        6.0.0
      • getNullOrdering

        public NullOrdering getNullOrdering()
        Returns the default ordering of null.
        Since:
        6.0.0
      • supportsNullPrecedence

        public boolean supportsNullPrecedence()
        Does this dialect support nulls first and nulls last?
      • requiresCastForConcatenatingNonStrings

        public boolean requiresCastForConcatenatingNonStrings()
        Does this dialect/database require casting of non-string arguments in the concat() function?
        Returns:
        true if casting using cast() is required
        Since:
        6.2
      • requiresFloatCastingOfIntegerDivision

        public boolean requiresFloatCastingOfIntegerDivision()
        Does this dialect require that integer divisions be wrapped in cast() calls to tell the db parser the expected type.
        Returns:
        True if integer divisions must be cast()ed to float
        Implementation Note:
        The culprit is HSQLDB.
      • supportsResultSetPositionQueryMethodsOnForwardOnlyCursor

        public boolean supportsResultSetPositionQueryMethodsOnForwardOnlyCursor()
        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.

        Returns:
        True if methods like ResultSet.isAfterLast() and ResultSet.isBeforeFirst() are supported for forward only cursors; false otherwise.
        Since:
        3.2
        API Note:
        This is highly driver dependent!
      • supportsCircularCascadeDeleteConstraints

        public boolean supportsCircularCascadeDeleteConstraints()
        Does this dialect support definition of cascade delete constraints which can cause circular chains?
        Returns:
        True if circular cascade delete constraints are supported; false otherwise.
        Since:
        3.2
      • supportsSubselectAsInPredicateLHS

        public boolean supportsSubselectAsInPredicateLHS()
        Is a subselect supported as the left-hand side (LHS) of an IN predicates?

        In other words, is syntax like <subquery> IN (1, 2, 3) supported?

        Returns:
        True if a subselect can appear as the LHS of an in-predicate; false otherwise.
        Since:
        3.2
      • supportsExpectedLobUsagePattern

        public boolean supportsExpectedLobUsagePattern()
        "Expected" LOB usage pattern is such that I can perform an insert via prepared statement with a parameter binding for a LOB value without crazy casting to JDBC driver implementation-specific classes.
        Returns:
        True if normal LOB usage patterns can be used with this driver; false if driver-specific hookiness needs to be applied.
        Since:
        3.2
        Implementation Note:
        Part of the trickiness here is the fact that this is largely driver-dependent. For example, Oracle (which is notoriously bad with LOB support in their drivers historically) actually does a pretty good job with LOB support as of the 10.2.x v ersions of their driver.
      • supportsUnboundedLobLocatorMaterialization

        public boolean supportsUnboundedLobLocatorMaterialization()
        Is it supported to materialize a LOB locator outside the transaction in which it was created?
        Returns:
        True if unbounded materialization is supported; false otherwise.
        Since:
        3.2
        Implementation Note:
        Again, part of the trickiness here is the fact that this is largely driver-dependent. All database I have tested which supportsExpectedLobUsagePattern() also support the ability to materialize a LOB outside the owning transaction.
      • supportsSubqueryOnMutatingTable

        public boolean supportsSubqueryOnMutatingTable()
        Does this dialect support referencing the table being mutated in a subquery? The "table being mutated" is the table referenced in an update or delete query. And so can that table then be referenced in a subquery of the update or 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)
        Returns:
        True if this dialect allows references the mutating table from a subquery.
      • supportsExistsInSelect

        public boolean supportsExistsInSelect()
        Does the dialect support an exists statement in the select clause?
        Returns:
        True if exists checks are allowed in the select clause; false otherwise.
      • doesReadCommittedCauseWritersToBlockReaders

        public boolean doesReadCommittedCauseWritersToBlockReaders()
        For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?
        Returns:
        True if writers block readers to achieve READ_COMMITTED; false otherwise.
      • doesRepeatableReadCauseReadersToBlockWriters

        public boolean doesRepeatableReadCauseReadersToBlockWriters()
        For the underlying database, is REPEATABLE_READ isolation implemented by forcing writers to wait for read locks to be released?
        Returns:
        True if readers block writers to achieve REPEATABLE_READ; false otherwise.
      • supportsBindAsCallableArgument

        public boolean supportsBindAsCallableArgument()
        Does this dialect support using a JDBC bind parameter as an argument to a function or procedure call?
        Returns:
        Returns true if the database supports accepting bind params as args, false otherwise. The default is true.
      • supportsTupleCounts

        public boolean supportsTupleCounts()
        Does this dialect support count(a,b)?
        Returns:
        True if the database supports counting tuples; false otherwise.
      • requiresParensForTupleCounts

        public boolean requiresParensForTupleCounts()
        If supportsTupleCounts() is true, does this dialect require the tuple to be delimited with parentheses?
        Returns:
        boolean
      • supportsTupleDistinctCounts

        public boolean supportsTupleDistinctCounts()
        Does this dialect support count(distinct a,b)?
        Returns:
        True if the database supports counting distinct tuples; false otherwise.
      • requiresParensForTupleDistinctCounts

        public boolean requiresParensForTupleDistinctCounts()
        If supportsTupleDistinctCounts() is true, does this dialect require the tuple to be delimited with parentheses?
        Returns:
        boolean
      • getInExpressionCountLimit

        public int getInExpressionCountLimit()
        Return the limit that the underlying database places on the number of elements in an IN predicate. If the database defines no such limits, simply return zero or a number smaller than zero.
        Returns:
        The limit, or a non-positive integer to indicate no limit.
      • getParameterCountLimit

        public int getParameterCountLimit()
        Return the limit that the underlying database places on the number of parameters that can be defined for a PreparedStatement. If the database defines no such limits, simply return zero or a number smaller than zero. By default, Dialect returns the same value as getInExpressionCountLimit().
        Returns:
        The limit, or a non-positive integer to indicate no limit.
      • forceLobAsLastValue

        public boolean forceLobAsLastValue()
        Must LOB values occur last in inserts and updates?
        Returns:
        boolean True if Lob values should be last, false if it does not matter.
        Implementation Note:
        Oracle is the culprit here, see HHH-4635.
      • isEmptyStringTreatedAsNull

        public boolean isEmptyStringTreatedAsNull()
        Return whether the dialect considers an empty string value to be null.
        Returns:
        boolean True if an empty string is treated as null, false otherwise.
        Implementation Note:
        Once again, the culprit is Oracle.
      • useFollowOnLocking

        public boolean useFollowOnLocking​(String sql,
                                          QueryOptions queryOptions)
        Some dialects have trouble applying pessimistic locking depending upon what other query options are specified (paging, ordering, etc). This method allows these dialects to request that locking be applied by subsequent selects.
        Returns:
        true indicates that the dialect requests that locking be applied by subsequent select; false (the default) indicates that locking should be applied to the main SQL statement.
        Since:
        5.2
      • getUniqueDelegate

        public UniqueDelegate getUniqueDelegate()
        Get the UniqueDelegate supported by this dialect
        Returns:
        The UniqueDelegate
      • getQueryHintString

        public String getQueryHintString​(String query,
                                         List<String> hintList)
        Apply a hint to the given SQL query.

        The entire query is provided, allowing full control over the placement and syntax of the hint.

        By default, ignore the hint and simply return the query.

        Parameters:
        query - The query to which to apply the hint.
        hintList - The hints to apply
        Returns:
        The modified SQL
      • getQueryHintString

        public String getQueryHintString​(String query,
                                         String hints)
        Apply a hint to the given SQL query.

        The entire query is provided, allowing full control over the placement and syntax of the hint.

        By default, ignore the hint and simply return the query.

        Parameters:
        query - The query to which to apply the hint.
        hints - The hints to apply
        Returns:
        The modified SQL
      • supportsOffsetInSubquery

        public boolean supportsOffsetInSubquery()
        Does this dialect support offset in subqueries?

        For example:

         select * from Table1 where col1 in (select col1 from Table2 order by col2 limit 1 offset 1)
         
        Returns:
        true if it does
      • supportsOrderByInSubquery

        public boolean supportsOrderByInSubquery()
        Does this dialect support the order by clause in subqueries?

        For example:

         select * from Table1 where col1 in (select col1 from Table2 order by col2 limit 1)
         
        Returns:
        true if it does
      • supportsSubqueryInSelect

        public boolean supportsSubqueryInSelect()
        Does this dialect support subqueries in the select clause?

        For example:

         select col1, (select col2 from Table2 where ...) from Table1
         
        Returns:
        true if it does
      • supportsInsertReturning

        public boolean supportsInsertReturning()
        Does this dialect fully support returning arbitrary generated column values after execution of an insert statement, using native SQL syntax?

        Support for identity columns is insufficient here, we require something like:

        1. insert ... returning ...
        2. select from final table (insert ... )
        Returns:
        true if InsertReturningDelegate works for any sort of primary key column (not just identity columns), or false if InsertReturningDelegate does not work, or only works for specialized identity/"autoincrement" columns
        Since:
        6.2
        See Also:
        InsertReturningDelegate
      • supportsInsertReturningRowId

        public boolean supportsInsertReturningRowId()
        Does this dialect supports returning the RowId column after execution of an insert statement, using native SQL syntax?
        Returns:
        true is the dialect supports returning the rowid column
        Since:
        6.5
        See Also:
        supportsInsertReturning()
      • supportsUpdateReturning

        public boolean supportsUpdateReturning()
        Does this dialect fully support returning arbitrary generated column values after execution of an update statement, using native SQL syntax?

        Defaults to the value of supportsInsertReturning() but can be overridden to explicitly disable this for updates.

        Since:
        6.5
        See Also:
        supportsInsertReturning()
      • supportsFetchClause

        public boolean supportsFetchClause​(FetchClauseType type)
        Does this dialect support the given FETCH clause type.
        Parameters:
        type - The fetch clause type
        Returns:
        true if the underlying database supports the given fetch clause type, false otherwise. The default is false.
      • supportsWindowFunctions

        public boolean supportsWindowFunctions()
        Does this dialect support window functions like row_number() over (..)?
        Returns:
        true if the underlying database supports window functions, false otherwise. The default is false.
      • supportsLateral

        public boolean supportsLateral()
        Does this dialect support the SQL lateral keyword or a proprietary alternative?
        Returns:
        true if the underlying database supports lateral, false otherwise. The default is false.
      • isJdbcLogWarningsEnabledByDefault

        public boolean isJdbcLogWarningsEnabledByDefault()
        Is JDBC statement warning logging enabled by default?
        Since:
        5.1
      • augmentPhysicalTableTypes

        public void augmentPhysicalTableTypes​(List<String> tableTypesList)
      • augmentRecognizedTableTypes

        public void augmentRecognizedTableTypes​(List<String> tableTypesList)
      • supportsPartitionBy

        public boolean supportsPartitionBy()
        Does is dialect support partition by?
        Since:
        5.2
      • getNationalizationSupport

        public NationalizationSupport getNationalizationSupport()
        Determines whether this database requires the use of explicitly nationalized character (Unicode) data types.

        That is, whether the use of Types.NCHAR, Types.NVARCHAR, and Types.NCLOB is required for nationalized character data.

      • supportsStandardArrays

        public boolean supportsStandardArrays()
        Does this database have native support for ANSI SQL standard arrays which are expressed in terms of the element type name: integer array.
        Returns:
        boolean
        Since:
        6.1
        Implementation Note:
        Oracle doesn't have this; we must instead use named array types.
      • useArrayForMultiValuedParameters

        public boolean useArrayForMultiValuedParameters()
        Does this database prefer to use array types for multi-valued parameters.
        Returns:
        boolean
        Since:
        6.3
      • getArrayTypeName

        public String getArrayTypeName​(String javaElementTypeName,
                                       String elementTypeName,
                                       Integer maxLength)
        The SQL type name for the array type with elements of the given type name.

        The ANSI-standard syntax is integer array.

        Since:
        6.1
      • supportsDistinctFromPredicate

        public boolean supportsDistinctFromPredicate()
        Does this dialect support some kind of distinct from predicate?

        That is, does it support syntax like:

         ... where FIRST_NAME IS DISTINCT FROM LAST_NAME
         
        Returns:
        True if this SQL dialect is known to support some kind of distinct from predicate; false otherwise
        Since:
        6.1
      • getPreferredSqlTypeCodeForArray

        public int getPreferredSqlTypeCodeForArray()
        The JDBC type code to use for mapping properties of basic Java array or Collection types.

        Usually SqlTypes.ARRAY or SqlTypes.VARBINARY.

        Returns:
        one of the type codes defined by SqlTypes.
        Since:
        6.1
      • getPreferredSqlTypeCodeForBoolean

        public int getPreferredSqlTypeCodeForBoolean()
        The JDBC type code to use for mapping properties of Java type boolean.

        Usually Types.BOOLEAN or Types.BIT.

        Returns:
        one of the type codes defined by Types.
      • supportsNonQueryWithCTE

        public boolean supportsNonQueryWithCTE()
        Does this dialect support insert, update, and delete statements with Common Table Expressions (CTEs)?
        Returns:
        true if non-query statements are supported with CTE
      • supportsRecursiveCTE

        public boolean supportsRecursiveCTE()
        Does this dialect/database support recursive CTEs?
        Returns:
        true if recursive CTEs are supported
        Since:
        6.2
      • supportsConflictClauseForInsertCTE

        public boolean supportsConflictClauseForInsertCTE()
        Does this dialect support the conflict clause for insert statements that appear in a CTE?
        Returns:
        true if conflict clause is supported
        Since:
        6.5
      • supportsValuesList

        public boolean supportsValuesList()
        Does this dialect support values lists of form VALUES (1), (2), (3)?
        Returns:
        true if values list are supported
      • supportsValuesListForInsert

        public boolean supportsValuesListForInsert()
        Does this dialect support values lists of form VALUES (1), (2), (3) in insert statements?
        Returns:
        true if values list are allowed in insert statements
      • supportsFromClauseInUpdate

        public boolean supportsFromClauseInUpdate()
        Does this dialect support the from clause for update statements?
        Returns:
        true if from clause is supported
        Since:
        6.5
      • supportsSkipLocked

        public boolean supportsSkipLocked()
        Does this dialect support SKIP_LOCKED timeout.
        Returns:
        true if SKIP_LOCKED is supported
      • supportsNoWait

        public boolean supportsNoWait()
        Does this dialect support NO_WAIT timeout.
        Returns:
        true if NO_WAIT is supported
      • supportsWait

        public boolean supportsWait()
        Does this dialect support WAIT timeout.
        Returns:
        true if WAIT is supported
      • inlineLiteral

        @Deprecated(since="6",
                    forRemoval=true)
        public String inlineLiteral​(String literal)
        Deprecated, for removal: This API element is subject to removal in a future version.
        This is no longer called
      • appendLiteral

        public void appendLiteral​(SqlAppender appender,
                                  String literal)
        Append a literal string to the given SqlAppender.
        API Note:
        Needed because MySQL has nonstandard escape characters
      • appendBinaryLiteral

        public void appendBinaryLiteral​(SqlAppender appender,
                                        byte[] bytes)
        Append a binary literal to the given SqlAppender.
      • addSqlHintOrComment

        public String addSqlHintOrComment​(String sql,
                                          QueryOptions queryOptions,
                                          boolean commentsEnabled)
        Modify the SQL, adding hints or comments, if necessary
      • prependComment

        protected String prependComment​(String sql,
                                        String comment)
        Prepend a comment to the given SQL fragment.
      • escapeComment

        public static String escapeComment​(String comment)
        Perform necessary character escaping on the text of the comment.
      • getGroupBySelectItemReferenceStrategy

        public SelectItemReferenceStrategy getGroupBySelectItemReferenceStrategy()
        Determine how selected items are referenced in the group by clause.
      • getMaxVarcharLength

        public int getMaxVarcharLength()
        The biggest size value that can be supplied as argument to a Types.VARCHAR-like type.

        For longer column lengths, use some sort of text-like type for the column.

      • getMaxNVarcharLength

        public int getMaxNVarcharLength()
        The biggest size value that can be supplied as argument to a Types.NVARCHAR-like type.

        For longer column lengths, use some sort of ntext-like type for the column.

      • getMaxVarbinaryLength

        public int getMaxVarbinaryLength()
        The biggest size value that can be supplied as argument to a Types.VARBINARY-like type.

        For longer column lengths, use some sort of image-like type for the column.

      • getMaxVarcharCapacity

        public int getMaxVarcharCapacity()
        The longest possible length of a Types.VARCHAR-like column.

        For longer column lengths, use some sort of clob-like type for the column.

      • getMaxNVarcharCapacity

        public int getMaxNVarcharCapacity()
        The longest possible length of a Types.NVARCHAR-like column.

        For longer column lengths, use some sort of nclob-like type for the column.

      • getMaxVarbinaryCapacity

        public int getMaxVarbinaryCapacity()
        The longest possible length of a Types.VARBINARY-like column.

        For longer column lengths, use some sort of blob-like type for the column.

      • getDefaultDecimalPrecision

        public int getDefaultDecimalPrecision()
        This is the default precision for a generated column of exact numeric type DECIMAL or NUMERIC mapped to a BigInteger or BigDecimal.

        Usually returns the maximum precision of the database, except when there is no such maximum precision, or the maximum precision is very high.

        Returns:
        the default precision, in decimal digits
        See Also:
        BigDecimalJavaType, BigIntegerJavaType
      • getDefaultIntervalSecondScale

        public int getDefaultIntervalSecondScale()
        This is the default scale for a generated column of type INTERVAL SECOND mapped to a Duration.

        Usually 9 (nanoseconds) or 6 (microseconds).

        Returns:
        the default scale, in decimal digits, of the fractional seconds field
        See Also:
        DurationJavaType
      • doesRoundTemporalOnOverflow

        public boolean doesRoundTemporalOnOverflow()
        Does this dialect round a temporal when converting from a precision higher to a lower one?
        Returns:
        true if rounding is applied, false if truncation is applied
      • getFloatPrecision

        public int getFloatPrecision()
        This is the default precision for a generated column mapped to a Java Float or float. That is, a value representing "single precision".

        Usually 24 binary digits, at least for databases with a conventional interpretation of the ANSI SQL specification.

        Returns:
        a value representing "single precision", usually in binary digits, but sometimes in decimal digits
      • getDoublePrecision

        public int getDoublePrecision()
        This is the default precision for a generated column mapped to a Java Double or double. That is, a value representing "double precision".

        Usually 53 binary digits, at least for databases with a conventional interpretation of the ANSI SQL specification.

        Returns:
        a value representing "double precision", usually in binary digits, but sometimes in decimal digits
      • supportsBitType

        public boolean supportsBitType()
        Does this dialect have a true SQL BIT type with just two values (0 and 1) or, even better, a proper SQL BOOLEAN type, or does Types.BIT get mapped to a numeric type with more than two values?
        Returns:
        true if there is a BIT or BOOLEAN type
      • supportsPredicateAsExpression

        protected boolean supportsPredicateAsExpression()
        Whether a predicate like a > 0 can appear in an expression context, for example, in a select list item.
      • generatedAs

        public String generatedAs​(String generatedAs)
        The generated as clause, or similar, for generated column declarations in DDL statements.
        Parameters:
        generatedAs - a SQL expression used to generate the column value
        Returns:
        The generated as clause containing the given expression
      • hasDataTypeBeforeGeneratedAs

        public boolean hasDataTypeBeforeGeneratedAs()
        Is an explicit column type required for generated as columns?
        Returns:
        true if an explicit type is required
      • getDisableConstraintsStatement

        public String getDisableConstraintsStatement()
        A SQL statement that temporarily disables foreign key constraint checking for all tables.
      • getEnableConstraintsStatement

        public String getEnableConstraintsStatement()
        A SQL statement that re-enables foreign key constraint checking for all tables.
      • getDisableConstraintStatement

        public String getDisableConstraintStatement​(String tableName,
                                                    String name)
        A SQL statement that temporarily disables checking of the given foreign key constraint.
        Parameters:
        tableName - the name of the table
        name - the name of the constraint
      • getEnableConstraintStatement

        public String getEnableConstraintStatement​(String tableName,
                                                   String name)
        A SQL statement that re-enables checking of the given foreign key constraint.
        Parameters:
        tableName - the name of the table
        name - the name of the constraint
      • canBatchTruncate

        public boolean canBatchTruncate()
        Does the truncate table statement accept multiple tables?
        Returns:
        true if it does
      • getTruncateTableStatements

        public String[] getTruncateTableStatements​(String[] tableNames)
        A SQL statement or statements that truncate the given tables.
        Parameters:
        tableNames - the names of the tables
      • getTruncateTableStatement

        public String getTruncateTableStatement​(String tableName)
        A SQL statement that truncates the given table.
        Parameters:
        tableName - the name of the table
      • getNativeParameterMarkerStrategy

        public ParameterMarkerStrategy getNativeParameterMarkerStrategy()
        Support for native parameter markers.

        This is generally dependent on both the database and the driver.

        Returns:
        May return null to indicate that the JDBC standard strategy should be used
      • appendDatetimeFormat

        public void appendDatetimeFormat​(SqlAppender appender,
                                         String format)
        Translate the given datetime format string from the pattern language defined by Java's DateTimeFormatter to whatever pattern language is understood by the native datetime formatting function for this database (often the to_char() function).

        Since it's never possible to translate every pattern letter sequences understood by DateTimeFormatter, only the following subset of pattern letters is accepted by Hibernate:

        • G: era
        • y: year of era
        • Y: year of week-based year
        • M: month of year
        • w: week of week-based year (ISO week number)
        • W: week of month
        • E: day of week (name)
        • e: day of week (number)
        • d: day of month
        • D: day of year
        • a: AM/PM
        • H: hour of day (24 hour time)
        • h: hour of AM/PM (12 hour time)
        • m: minutes
        • s: seconds
        • z,Z,x: timezone offset

        In addition, punctuation characters and single-quoted literal strings are accepted.

        Appends a pattern accepted by the function that formats dates and times in this dialect to a SQL fragment that is being constructed.

      • appendIntervalLiteral

        public void appendIntervalLiteral​(SqlAppender appender,
                                          Duration literal)
        Append a literal SQL interval representing the given Java Duration.
      • appendUUIDLiteral

        public void appendUUIDLiteral​(SqlAppender appender,
                                      UUID literal)
        Append a literal SQL uuid representing the given Java UUID.

        This is usually a cast() expression, but it might be a function call.

      • supportsTemporalLiteralOffset

        public boolean supportsTemporalLiteralOffset()
        Does this dialect supports timezone offsets in temporal literals.
      • rowId

        public String rowId​(String rowId)
        The name of a rowid-like pseudo-column which acts as a high-performance row locator, or null if this dialect has no such pseudo-column.

        If the rowid-like value is an explicitly-declared named column instead of an implicit pseudo-column, and if the given name is nonempty, return the given name.

        Parameters:
        rowId - the name specified by RowId.value(), which is ignored if getRowIdColumnString(java.lang.String) is not overridden
      • rowIdSqlType

        public int rowIdSqlType()
        The JDBC type code of the rowid-like pseudo-column which acts as a high-performance row locator.
        Returns:
        Types.ROWID by default
      • getRowIdColumnString

        public String getRowIdColumnString​(String rowId)
        If this dialect requires that the rowid column be declared explicitly, return the DDL column definition.
        Returns:
        the DDL column definition, or null if the rowid is an implicit pseudo-column
      • getFunctionalDependencyAnalysisSupport

        public FunctionalDependencyAnalysisSupport getFunctionalDependencyAnalysisSupport()
        Get this dialect's level of support for primary key functional dependency analysis within GROUP BY and ORDER BY clauses.