Session Number: 1215
Track: 5-Data Warehousing and SQL
Session Type: Best Practices, Tips & Tricks
Primary Presenter: Mauro Pagano [Accenture Enkitec Group]
Time: Jan 26, 2016 (10:15 AM - 11:05 AM)
Session level: Intermediate
Abstract (250 words or less):
One of the great things about using an optimizer is the benefit of seeing your SQL statement transformed to be more efficient and faster. The CBO is able to change the SQL statement in dozens of ways, often multiple times just for a single SQL statement. This is probably the main reason why analyzing the CBO trace (10053) is so painful and scary to many: who likes to read a million-row trace? This session will focus on the mechanics behind the query transformation framework and will illustrate an analytical way to attack any CBO trace and decompose it into smaller, easier-to-analyze pieces.