Generating the Database Statistics

You need to gather statistics for all the tables whose partitions are dropped and indexes are rebuilt. To generate the database statistics for an individual table, use the following statement:

BEGIN
DBMS_STATS.GATHER_TABLE_STATS(OWNNAME=>'CISADM', 
TABNAME=>'<Table_Name>', GRANULARITY=>'ALL', CASCADE=>TRUE, METHOD_OPT=> 
'FOR ALL COLUMNS SIZE AUTO', DEGREE=>32);
END;