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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: ReferenceThe HCL OneDB™ Guide to SQL: Reference contains the reference information for the system catalog tables, data types, and environment variables of the HCL OneDB™ dialect of the SQL language, as implemented in HCL OneDB™. These topics also include information about the stores_demo, sales_demo, and superstore_demo databases that are included with HCL OneDB™.
Environment variablesVarious environment variables affect the functionality of your HCL OneDB™ products. You can set environment variables that identify your terminal, specify the location of your software and define other parameters.
Environment variables in HCL OneDB™ productsThe topics that follow discuss (in alphabetic order) environment variables that HCL OneDB™ database server products and their utilities use.
OPT_GOAL environment variable (UNIX™)

OPT_GOAL environment variable (UNIX)

Set the OPT_GOAL environment variable in the user environment, before you start an application, to specify the query performance goal for the optimizer.

0: Specifies user-response-time optimization.
-1: Specifies total-query-time optimization.

The default behavior is for the optimizer to use query plans that optimize the total query time.

You can also specify the optimization goal for individual queries with optimizer directives or for a session with the SET OPTIMIZATION statement.

Both methods take precedence over the OPT_GOAL environment variable setting. You can also set the OPT_GOAL configuration parameter for the HCL OneDB™ system; this method has the lowest level of precedence.

For more information about optimizing queries for your database server, see your HCL OneDB Performance Guide. For information about the SET OPTIMIZATION statement, see the HCL OneDB Guide to SQL: Syntax.