Optimizing query performance with query hints
If your reports are taking too long to run, you can specify query hints to optimize the report queries.
The hints control how the query is executed. If a query hint does not produce the results that you intended, check the governors that are specified in the IBM Cognos Framework Manager model.
Query hints can also be added to the report specification in the Cognos® Analytics Software Development Kit (SDK). For more information, see Use query hints.
About this task
Cognos Framework Manager models might include governors that optimize query performance. A governor is a set of rules to limit user activities, such as the execution of reports, which can either take too long to run or consume too many resources. By default, at run time Cognos Analytics applies governors that are set in the model to all queries that query metadata from that model. For more information about governors, see the Framework Manager User Guide.
Similarly, you can add hints to optimize how Cognos Analytics runs a specific query in a report. Like governors, query hints can be applied to sorting, joins, row retrieval, and other aspects of the query. The governors can also affect how Cognos Analytics builds the SQL for the query. In general, hints do not return errors whereas governors return errors when limits set in them are exceeded.