No matter how many times I have worked with Outlines, Baselines and Profiles, I keep having to look up reminders as to the differences between these three.
There is seemingly no end to articles to the number of articles and blog that tell you what needs to be licensed, how to use them, and which version of Oracle where each made its debut appearance.
This blog will discuss none of that. This brief article simply shows the definitions of each from the Glossary for the most current version of the Oracle databases. As of this writing that version is 18.104.22.168.
And here they are.
A stored outline is simply a set of hints for a SQL statement. The hints in stored outlines direct the optimizer to choose a specific plan for the statement.
SQL plan baseline
A SQL baselines is a set of one or more accepted plans for a repeatable SQL statement. Each accepted plan contains a set of hints, a plan hash value, and other plan-related information. SQL plan management uses SQL plan baselines to record and evaluate the execution plans of SQL statements over time.
A SQL profile is a set of auxiliary information built during automatic tuning of a SQL statement. A SQL profile is to a SQL statement what statistics are to a table. The optimizer can use SQL profiles to improve cardinality and selectivity estimates, which in turn leads the optimizer to select better plans.