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4.3. SQL Translation Extension

The JDBCExcecutionFactory provides several methods to modify the command and the string form of the resulting syntax before it is sent to the JDBC driver, including:
  • Change basic SQL syntax options. See the useXXX methods, e.g. useSelectLimit returns true for SQLServer to indicate that limits are applied in the SELECT clause.
  • Register one or more FunctionModifiers that define how a scalar function is to be modified or transformed.
  • Modify a LanguageObject (see the translate, translateXXX, and FunctionModifier.translate methods). Modify the passed in object and return null to indicate that the standard syntax output will be used.
  • Change the way SQL strings are formed for a LanguageObject (see the translate, translateXXX, and FunctionModifier.translate methods). This returns a list of parts which can contain strings and LanguageObjects. These are appended to the SQL string in order. If the incoming LanguageObject appears in the returned list it is not translated again.