Purpose

The Explain Plan statement can be used with any query to retrieve a detailed list of the elements in the execution plan. Explain Plan generates a result set with a single column named OPERATION. The individual elements that comprise the plan are returned as rows in the result set.

Syntax

EXPLAIN PLAN FOR {SELECT ... | DELETE ... | INSERT ... | UPDATE ...}

The returned list of elements includes the indexes used for performing the query and can be used to optimize the query.