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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.
The directive Specification

The directive Specification

Each directive specification in the SAVE EXTERNAL DIRECTIVES statement must follow the syntax of the Optimizer Directives segment, as described in Optimizer Directives, except that if you specify more than one directive, you must separate them in the directives list by a blank character, rather than by a comma ( , ) symbol, as in the following example:

SAVE EXTERNAL DIRECTIVES /*+ AVOID_INDEX (table1 index1)*/ /*+ FULL(table1) */ 
       ACTIVE FOR 
           SELECT /*+ INDEX( table1 index1 ) */  col1, col2 
               FROM table1, table2 WHERE table1.col1 = table2.col1;

This example associates AVOID_INDEX and FULL directives with the specified query. The inline INDEX directive is ignored by the query optimizer when the external directives are applied to a query that matches the SELECT statement.