BEGIN DBMS_STATS.DELETE_TABLE_STATS(, ); END;. SAMPLEFOO. BEGIN DBMS_STATS. The DBMS_STATS package allows you to publish or delete pending statistics, as show below. FOR ALL COLUMNS SIZE AUTO allows the GATHER_ procedures to gather statistics on all existing column groups for the specified object. The dbms_stats utility does a far better job in estimating statistics, especially for large partitioned tables, and the better statistics result in faster SQL execution plans.
:Improvement of AUTO sampling statistics gathering feature in Oracle 11g — beginning of translation — Oracle 11g. DBMS_STATS.GATHER_TABLE_STATS (STATT). This procedure gathers table and column (and index) statistics. It attempts to parallelize as much of the work as possible, but there are some restrictions as described in the individual parameters. To gather statistics on an object in another schema you need the ANALYZE ANY system privilege. I appears that the user that runs your procedure has that privilege, but granted through a role. As the documentation says:.
DBMS_STATS package, which lets you collect statistics in parallel, collect global statistics for partitioned objects, and fine tune your statistics collection in other ways. This package is concerned with optimizer statistics only. dbms_stats is essential to good SQL performance, and it should always be used before adjusting any of the Oracle optimizer initialization parameters. Quick question, after populating my table, I noticed through my explain plan that indexes, in most cases, only seems to take effect after I perform GATHER_TABLE_STATS: Exec. For years Oracle has been telling us to use the DBMS_STATS package instead of the ANALYZE command to gather statistics to be used by the Oracle optimizer. Many of us have heeded this advice and switched from using ANALYZE for scheduled statistics-gathering jobs to using DBMS_STATS.
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The second post showed a completely different strategy we use on many tables of gathering no stats at all at the Table and Partition level, but gathering Subpartition statistics and having Oracle aggregate them up to the higher levels in an attempt to reduce stats gathering activity. The DBMS_STATS package can gather statistics on table and indexes, and well as individual columns and partitions of tables. When you generate statistics for a table, column, or index, if the data dictionary already contains statistics for the object, then Oracle updates the existing statistics. DBMS_STATS.GATHER_TABLE_STATS( OWNNAME ‘hoge’ –,TABNAME ‘SAMPLE_TABLE’ –,ESTIMATE_PERCENT 10 –,CASCADE TRUE –,NO_INVALIDATE FALSE — );. Oracle implicitly determines which objects need new statistics, and determines how to gather those statistics. When GATHER AUTO is specified, the only additional valid parameters are stattab, statid, objlist and statown; all other parameter settings are ignored. DBMS_STATS.GATHER_SCHEMA_STATS In Oracle Database when there is something called Cost Based Optimizer (CBO) which other than doing many things also does query optimization.