The procedure is still available,
however, for backward compatibility.
You can use private outlines, which are seen only within your current session. Changes made
to a private outline do not affect any other users. To enable private outline editing, set the USE_
Chapter 5: Developing and Implementing Applications 143
PRIVATE_OUTLINES initialization parameter to TRUE. Use the REFRESH_PRIVATE_OUTLINE
procedure to have your changes take effect for the in-memory versions of the outlines.
Using SQL Profiles
As of Oracle 10g, you can use SQL profiles to further refine the SQL execution plans chosen by
the optimizer. SQL profiles are particularly useful when you are attempting to tune code that you
do not have direct access to (for example, within a packaged application). The SQL profile consists
of statistics that are specific to the statement, allowing the optimizer to know more about the exact
selectivity and cost of the steps in the execution plan.
SQL profiling is part of the automatic tuning capability that I will describe in Chapter 8. Once
you accept a SQL profile recommendation, it is stored in the data dictionary. As with stored outlines,
you can use a category attribute to control its usage. See Chapter 8 for further details on the use of
the automatic tools for detection and diagnosis of SQL performance issues.
Sizing Database Objects
Choosing the proper space allocation for database objects is critical. Developers should begin
estimating space requirements before the first database objects are created.
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