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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
SAVE EXTERNAL DIRECTIVES statementUse the SAVE EXTERNAL DIRECTIVES statement to create external optimizer directives for a specified query, and save the directives in the database. These directives are applied automatically to subsequent instances of the same query. This statement is an extension to the ANSI/ISO standard for SQL.
External optimizer directivesExternal directives that the SAVE EXTERNAL DIRECTIVES statement associates with the text of a query can improve performance in some queries for which the default behavior of the query optimizer is not satisfactory.

External optimizer directives

External directives that the SAVE EXTERNAL DIRECTIVES statement associates with the text of a query can improve performance in some queries for which the default behavior of the query optimizer is not satisfactory.

External optimizer directives are similar to inline optimizer directives that are embedded within a query. However, unlike inline directives, external directives can be applied without revising or recompiling existing applications.