Changing the type of SQL
When choosing the type of SQL in which to generate a data source query subject, you must weigh the following factors and decide which are most important.
Type |
Advantage |
Disadvantage |
---|---|---|
Cognos® SQL |
Cognos SQL improves query subject performance; for example, by removing unused elements at query time. SQL works on any supported database. |
You cannot enter non-standard SQL. |
Native SQL |
Performance is optimized across all related query subjects. You can use SQL that is specific to your database. |
You cannot use SQL that the data source does not support for subqueries. The SQL may not work on a different database type. |
Pass- Through SQL |
You can enter any SQL supported by the database. |
There is no opportunity for Framework Manager to automatically optimize performance. The SQL may not work on a different data source. |