User-Defined Function Calls in SQL: One, Two…Many?
-
Posted by Quest Customer Learning Team
- Last updated 7/13/20
- Share
Quest Forum Digital Event 2020
Every database developer knows that PL/SQL functions can be used in SQL queries. However, not many are aware of the measurable cost of SQL-to-PL/SQL context switches. Even fewer can definitively answer how many times their functions will be called (depending upon the complexity of queries or portion of the query where the function is located). This presentation sheds some light on this gray area. The answer is actually very simple: the number of calls is driven by the cardinality of involved tables plus the final execution plan of your query (after all query-transformation steps). Unfortunately, GUESSING what exactly the Cost-Based Optimizer will do to your query is very difficult. This presentation will show you how to KNOW rather than guess and how to use this knowledge to optimize the performance of your database.
Watch the full-length video
You’ve reached the ultimate Oracle customer network—exclusively for Quest Corporate and Professional members.
Join Quest to unlock access to strategic content centers, event replays, exclusive programming, and expert insights—all designed to help Oracle users like you go further, faster.
Whether you're on JD Edwards, PeopleSoft, or Oracle Cloud, Quest connects you with a powerful peer network and Oracle experts so you can make smarter decisions, drive innovation, and get more from your investment.
Quest is where Oracle customers connect, learn, and lead with confidence. Ready to join them?
