First-Rows Optimization

The SQL produced by IBM® Cognos® Analytics - Reporting depends on the report format you choose. For example, if you specify HTML format, first-rows optimization is requested. All-rows is requested if you specify PDF.

It is important for database administrators and programmers to remember that Cognos Analytics - Reporting does not always use first-rows optimization. If you assume first-rows optimization is always requested, this can cause the RDBMS optimizer to process the query differently than you expect.