Function Calls in SQL - Black Box for the Optimizer?
Track
Database & Infrastructure
Date and time
Thursday, 19. October 2023., 11:55
Room
Hall A
Duration
45'
Functions in SQL are a useful and popular feature that is often used. However, little attention is often paid to performance aspects. A function call or an expression in a WHERE condition is a challenge for the query optimizer that often leads to unsuitable execution plans and bad response times. For PL/SQL functions called from SQL, the situation is even more complex. If used incorrectly, they can lead to massive performance degradation.In this presentation, I will show different possibilities to support the optimizer in function calls to generate better execution plans. Furthermore, I will explain how PL/SQL functions can be used optimally in SQL queries and which performance killers must be avoided. Of course, all this will be demonstrated with live examples and stories from the field.
Lecture details
About speaker
Dani Schnider, author
Dani Schnider works as Principal Oracle & DWH Consultant for Callista, a Swiss IT service provider for consulting and engineering. He has been working in database consulting for over 20 years, from 1999 to 2022 for Trivadis in Switzerland. Dani works with Oracle databases since 1994, since 1997 mainly in data warehouse projects. His tasks include DWH architecture reviews, data modeling, ETL development and performance optimization in Oracle databases. Dani is Oracle ACE Director and co-author of the books Data Warehousing mit Oracle ? Business Intelligence in der Praxis and Data Warehouse Blueprints, both published in German by Hanser-Verlag. On his blog, he writes about design and performance topics related to Oracle data warehouses. He is a regular speaker at international Oracle user group conferences.
T-Shirt Sponsor
Venue Sponsor
Media Sponsor
HrOUG.hr
The conference is organized by the Croatian Association of Oracle users. More about the association can be found at Hroug.hr.