Lets Oracle decide whether to collect statistics for indexes or not The DBMS_STATS package uses the constants shown in Table 140-1: Maxdiffpct number) - max stats difference (percentage) Type for displaying statistics difference report: TYPE DiffRepElem IS RECORD ( Objtype VARCHAR2(6), - 'TABLE' or 'INDEX' Types for listing stale tables include: TYPE ObjectElem IS RECORD ( TYPE dblarray IS VARRAY(256) OF BINARY_DOUBLE TYPE fltarray IS VARRAY(256) OF BINARY_FLOAT TYPE rawarray IS VARRAY(256) OF RAW(2000) TYPE chararray IS VARRAY(256) OF VARCHAR2(4000) Types for the minimum and maximum values and histogram endpoints include: TYPE numarray IS VARRAY(256) OF NUMBER See Also: Oracle Database Performance Tuning Guide for more information about "Managing Optimizer Statistics". You can also use DBMS_STATS to gather statistics in parallel Only statistics stored in the dictionary have an impact on the cost-based optimizer. You can also collect and manage user-defined statistics for tables and domain indexes using this package.įor example, if the DELETE_COLUMN_STATS procedure is invoked on a column for which an association is defined, user-defined statistics for that column are deleted in addition to deletion of the standard statistics. The statistics of interest to be viewed or modified can reside in the dictionary or in a table created in the user's schema for this purpose.
Given that Oracle sets automatic statistics collection of this kind on by default, this package is intended for only specialized cases. This package is concerned with optimizer statistics only. The Oracle RDBMS allows you to collect statistics of many different kinds as an aid to improving performance.
This section contains topics which relate to using the DBMS_STATS package.
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