Oracle 10g Data Dictionary Table Statistics

To collect statistics on dictionary objects, execute the following statements. The collection process can be done in different formats.

Format (1)
SQL> EXEC DBMS_STATS.GATHER_SCHEMA_STATS ('SYS');

Format (2)
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS (gather_sys=>TRUE);

Format (3)
SQL> EXEC DBMS_STATS.GATHER_DICTIONARY_STATS;

As seen in the above examples, the gather_schema_stats procedure accepts the sys argument to perform statistics collections. In case of the gather_database_stats procedure, there is a new argument gather_sys whose default value is FALSE. When needed, you can set it to TRUE and execute the procedure.

There is another procedure, delete_dictionary_stats, which allows you to remove data dictionary stats.

When you execute the gather_dictionary_stats procedure, it gathers statistics from the SYS and SYSTEM schemas, as well as any other schemas that are related, such as OUTLN or DBSNMP schemas.