Abstract
An execution plan describes how Oracle will retrieve the data to satisfy the results of a query. When you submit a SQL statement, the query optimizer quickly produces several execution plans and will determine which plan is most efficient. In most scenarios, the prior behavior results in a well-performing execution plan. However, you will encounter situations where you know additional details about your environment and need to adjust the optimizer’s choice of an execution plan. Listed next are features you can use to influence the decision path the optimizer uses when selecting a plan:
-
Initialization parameters
-
Statistics
-
Hints
-
SQL profiles
-
SQL plan management (plan baselines)
-
Stored outlines (deprecated in favor of plan baselines)
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Rights and permissions
Copyright information
© 2011 Sam R. Alapati, Darl Kuhn, and Bill Padfield
About this chapter
Cite this chapter
Alapati, S.R., Kuhn, D., Padfield, B. (2011). Execution Plan Optimization and Consistency. In: Oracle Database 11g Performance Tuning Recipes. Apress, Berkeley, CA. https://doi.org/10.1007/978-1-4302-3663-4_12
Download citation
DOI: https://doi.org/10.1007/978-1-4302-3663-4_12
Publisher Name: Apress, Berkeley, CA
Print ISBN: 978-1-4302-3662-7
Online ISBN: 978-1-4302-3663-4
eBook Packages: Professional and Applied ComputingProfessional and Applied Computing (R0)Apress Access Books