Package org.eclipse.persistence.platform.database

Class MySQLPlatform

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable, CorePlatform<ConversionManager>, Platform
    public class MySQLPlatform
extends DatabasePlatform

    Purpose: Provides MySQL specific behavior.

    Responsibilities:

    • Native SQL for Date, Time, & Timestamp.
    • Native sequencing.
    • Mapping of class types to database types for the schema framework.
    • Pessimistic locking.
    • Platform specific operators.
    Since:
    OracleAS TopLink 10g (10.1.3)
    See Also:
    Serialized Form

    • Constructor Detail

      • MySQLPlatform

        public MySQLPlatform()

    • Method Detail

      • initializeConnectionData

        public void initializeConnectionData​(java.sql.Connection connection)
                              throws java.sql.SQLException
        Description copied from class: DatabasePlatform
        INTERNAL: Allow initialization from the connection.
        Overrides:
        initializeConnectionData in class DatabasePlatform
        Throws:
        java.sql.SQLException

      • isFractionalTimeSupported

        public boolean isFractionalTimeSupported()

      • appendDate

        protected void appendDate​(java.sql.Date date,
                          java.io.Writer writer)
                   throws java.io.IOException
        Appends an MySQL specific date if usesNativeSQL is true otherwise use the ODBC format. Native FORMAT: 'YYYY-MM-DD'
        Overrides:
        appendDate in class DatabasePlatform
        Throws:
        java.io.IOException

      • appendTime

        protected void appendTime​(java.sql.Time time,
                          java.io.Writer writer)
                   throws java.io.IOException
        Appends an MySQL specific time if usesNativeSQL is true otherwise use the ODBC format. Native FORMAT: 'HH:MM:SS'.
        Overrides:
        appendTime in class DatabasePlatform
        Throws:
        java.io.IOException

      • appendTimestamp

        protected void appendTimestamp​(java.sql.Timestamp timestamp,
                               java.io.Writer writer)
                        throws java.io.IOException
        Appends an MySQL specific Timestamp, if usesNativeSQL is true otherwise use the ODBC format. Native Format: 'YYYY-MM-DD HH:MM:SS'
        Overrides:
        appendTimestamp in class DatabasePlatform
        Throws:
        java.io.IOException

      • appendCalendar

        protected void appendCalendar​(java.util.Calendar calendar,
                              java.io.Writer writer)
                       throws java.io.IOException
        Appends an MySQL specific Timestamp, if usesNativeSQL is true otherwise use the ODBC format. Native Format: 'YYYY-MM-DD HH:MM:SS'
        Overrides:
        appendCalendar in class DatabasePlatform
        Throws:
        java.io.IOException

      • buildFieldTypes

        protected java.util.Hashtable buildFieldTypes()
        Return the mapping of class types to database types for the schema framework.
        Overrides:
        buildFieldTypes in class DatabasePlatform

      • computeMaxRowsForSQL

        public int computeMaxRowsForSQL​(int firstResultIndex,
                                int maxResults)
        INTERNAL: Use the JDBC maxResults and firstResultIndex setting to compute a value to use when limiting the results of a query in SQL. These limits tend to be used in two ways. 1. MaxRows is the index of the last row to be returned (like JDBC maxResults) 2. MaxRows is the number of rows to be returned MySQL uses case #2 and therefore the maxResults has to be altered based on the firstResultIndex
        Overrides:
        computeMaxRowsForSQL in class DatabasePlatform
        Parameters:
        firstResultIndex -
        maxResults -
        See Also:
        MySQLPlatform

      • isForUpdateCompatibleWithDistinct

        public boolean isForUpdateCompatibleWithDistinct()
        Description copied from class: DatabasePlatform
        INTERNAL: Indicates whether SELECT DISTINCT ... FOR UPDATE is allowed by the platform (Oracle doesn't allow this).
        Overrides:
        isForUpdateCompatibleWithDistinct in class DatabasePlatform

      • logOperator

        protected ExpressionOperator logOperator()
        INTERNAL: Create the 10 based log operator for this platform.

      • toNumberOperator

        protected ExpressionOperator toNumberOperator()
        INTERNAL: Build MySQL equivalent to TO_NUMBER.

      • toDateOperator

        protected ExpressionOperator toDateOperator()
        INTERNAL: Build MySQL equivalent to TO_DATE.

      • toCharOperator

        protected ExpressionOperator toCharOperator()
        INTERNAL: Build MySQL equivalent to TO_CHAR.

      • dateToStringOperator

        protected ExpressionOperator dateToStringOperator()
        INTERNAL: Build MySQL equivalent to TO_CHAR.

      • leftTrim2

        protected ExpressionOperator leftTrim2()
        INTERNAL: Build MySQL equivalent to LTRIM(string_exp, character). MySQL: TRIM(LEADING character FROM string_exp)

      • rightTrim2

        protected ExpressionOperator rightTrim2()
        INTERNAL: Build MySQL equivalent to RTRIM(string_exp, character). MySQL: TRIM(TRAILING character FROM string_exp)

      • currentDateOperator

        protected ExpressionOperator currentDateOperator()
        INTERNAL: Create the current date operator for this platform.

      • shouldUseJDBCOuterJoinSyntax

        public boolean shouldUseJDBCOuterJoinSyntax()
        INTERNAL: JDBC defines an outer join syntax which many drivers do not support. So we normally avoid it.
        Overrides:
        shouldUseJDBCOuterJoinSyntax in class DatabasePlatform

      • supportsIdentity

        public boolean supportsIdentity()
        INTERNAL: Indicates whether the platform supports identity. MySQL supports native sequencing through AUTO_INCREMENT field types.
        Overrides:
        supportsIdentity in class DatasourcePlatform

      • supportsCountDistinctWithMultipleFields

        public boolean supportsCountDistinctWithMultipleFields()
        INTERNAL: Indicates whether the platform supports the count distinct function with multiple fields.
        Overrides:
        supportsCountDistinctWithMultipleFields in class DatabasePlatform

      • requiresTableInIndexDropDDL

        public boolean requiresTableInIndexDropDDL()
        INTERNAL: Return if this database requires the table name when dropping an index.
        Overrides:
        requiresTableInIndexDropDDL in class DatabasePlatform

      • supportsGlobalTempTables

        public boolean supportsGlobalTempTables()
        INTERNAL: MySQL supports temp tables for update-all, delete-all queries.
        Overrides:
        supportsGlobalTempTables in class DatabasePlatform

      • supportsIndividualTableLocking

        public boolean supportsIndividualTableLocking()
        INTERNAL: Indicates whether locking clause could be selectively applied only to some tables in a ReadQuery. Example: the following locks the rows in SALARY table, doesn't lock the rows in EMPLOYEE table: on Oracle platform (method returns true): SELECT t0.EMP_ID..., t1.SALARY FROM EMPLOYEE t0, SALARY t1 WHERE ... FOR UPDATE t1.SALARY on SQLServer platform (method returns true): SELECT t0.EMP_ID..., t1.SALARY FROM EMPLOYEE t0, SALARY t1 WITH (UPDLOCK) WHERE ...
        Overrides:
        supportsIndividualTableLocking in class DatabasePlatform

      • supportsAutoConversionToNumericForArithmeticOperations

        public boolean supportsAutoConversionToNumericForArithmeticOperations()
        Some db allow VARCHAR db field to be used in arithmetic operations automatically converting them to numeric: UPDATE OL_PHONE SET PHONE_ORDER_VARCHAR = (PHONE_ORDER_VARCHAR + 1) WHERE ... SELECT ... WHERE ... t0.MANAGED_ORDER_VARCHAR BETWEEN 1 AND 4 ...
        Overrides:
        supportsAutoConversionToNumericForArithmeticOperations in class DatabasePlatform

      • getCreateTempTableSqlPrefix

        protected java.lang.String getCreateTempTableSqlPrefix()
        INTERNAL: MySQL temp table syntax, used for update-all, delete-all queries.
        Overrides:
        getCreateTempTableSqlPrefix in class DatabasePlatform

      • getDropDatabaseSchemaString

        public java.lang.String getDropDatabaseSchemaString​(java.lang.String schema)
        Return the drop schema definition. Subclasses should override as needed.
        Overrides:
        getDropDatabaseSchemaString in class DatabasePlatform

      • shouldPrintStoredProcedureArgumentNameInCall

        public boolean shouldPrintStoredProcedureArgumentNameInCall()
        INTERNAL: MySQL stored procedure calls do not require the argument name be printed in the call string e.g. call MyStoredProc(?) instead of call MyStoredProc(myvariable = ?)
        Overrides:
        shouldPrintStoredProcedureArgumentNameInCall in class DatabasePlatform

      • writeUpdateOriginalFromTempTableSql

        public void writeUpdateOriginalFromTempTableSql​(java.io.Writer writer,
                                                DatabaseTable table,
                                                java.util.Collection pkFields,
                                                java.util.Collection assignedFields)
                                         throws java.io.IOException
        INTERNAL: Writes MySQL specific SQL for accessing temp tables for update-all queries.
        Overrides:
        writeUpdateOriginalFromTempTableSql in class DatabasePlatform
        Throws:
        java.io.IOException

      • requiresProcedureBrackets

        public boolean requiresProcedureBrackets()
        Used for stored procedure creation: MySQL platforms need brackets around arguments declaration even if no arguments exist.
        Overrides:
        requiresProcedureBrackets in class DatabasePlatform

      • printStoredFunctionReturnKeyWord

        public void printStoredFunctionReturnKeyWord​(java.io.Writer writer)
                                      throws java.io.IOException
        INTERNAL: Prints return keyword for StoredFunctionDefinition: CREATE FUNCTION StoredFunction_In (P_IN BIGINT) RETURN BIGINT The method was introduced because MySQL requires "RETURNS" instead: CREATE FUNCTION StoredFunction_In (P_IN BIGINT) RETURNS BIGINT
        Overrides:
        printStoredFunctionReturnKeyWord in class DatabasePlatform
        Throws:
        java.io.IOException

      • getTableExistsQuery

        protected DataReadQuery getTableExistsQuery​(TableDefinition table)
        INTERNAL: Returns query to check whether given table exists. Query execution returns a row when table exists or empty result otherwise.
        Overrides:
        getTableExistsQuery in class DatabasePlatform
        Parameters:
        table - database table meta-data
        Returns:
        query to check whether given table exists

      • checkTableExists

        public boolean checkTableExists​(DatabaseSessionImpl session,
                                TableDefinition table,
                                boolean suppressLogging)
        INTERNAL: Executes and evaluates query to check whether given table exists. Returned value depends on returned result set being empty or not.
        Overrides:
        checkTableExists in class DatabasePlatform
        Parameters:
        session - current database session
        table - database table meta-data
        suppressLogging - whether to suppress logging during query execution
        Returns:
        value of true if given table exists or false otherwise