Home
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.
Other syntax segmentsThese topics describe syntax segments, which are language elements, such as database object names or optimizer directives, that appear as a subdiagram reference in the syntax diagrams of some SQL or SPL statements.
Optimizer DirectivesThe Optimizer Directives segment specifies keywords that you can use to partially or fully specify the query plan of the optimizer. Use this segment whenever you see a reference to Optimizer Directives in a syntax diagram.
Restrictions on Optimizer Directives

Restrictions on Optimizer Directives

You can specify optimizer directives for any query in a DELETE, SELECT, or UPDATE statement, unless it includes any of the following syntax elements:

A query accessing a table in a database of a remote database server instance
In , a statement with the WHERE CURRENT OF cursor clause

For queries that use ANSI/ISO-compliant syntax to specify a join, the query optimizer does not follow some directives:

The join-method directives (USE_NL, AVOID_NL, USE_HASH, AVOID_HASH, /BUILD, and /PROBE) are ignored, except in cases where the optimizer rewrites the query so that it is no longer uses the ANSI/ISO syntax.
The join-order directive (ORDERED) is ignored in ANSI-compliant joined queries that specify the RIGHT OUTER JOIN or FULL OUTER JOIN keywords.

Have feedback?
Google Analytics is used to store comments and ratings. To provide a comment or rating for a topic, click Accept All Cookies or Allow All in Cookie Preferences in the footer of this page.