Thursday, July 7, 2011

transfer stats from one schema to another

exporting from schema ORIG_USER and importing into MYUSER

1. create stattab DBMS_STATS.CREATE_STAT_TABLE(ownname=>'ORIG_USER',stattab=>'STATS_FOR_TEST');
2. create table with list of tables: create table test_tabs(object_name varchar2(200));
insert into test_tabs (select ...)

3. export statsselect 'exec dbms_stats.export_table_stats(ownname=>''ORIG_USER'',tabname=>'''|| object_name ||''',stattab=>''STATS_FOR_TEST'');' cmd from (select distinct object_name from test_tabs) t;
4. delete stats on target schemaselect 'exec dbms_stats.import_table_stats(ownname=>''MYUSER'',tabname=>'''|| object_name ||''',force=>true);' cmd from (select distinct object_name from test_tabs) t;
5. copy table with stats: create table myuser.STATS_FOR_TEST as (select * from orig_user.STATS_FOR_TEST);
6. modify the MYUSER.STATS_FOR_TEST:update stats_for_test set c5='MYUSER';
update stats_for_test set ch1 = ora_hash(ch1) where ch1 is not null; <== to mask histogram values

7. import statsselect 'exec dbms_stats.import_table_stats(ownname=>''MYUSER'',tabname=>'''|| object_name ||''',stattab=>''STATS_FOR_TEST'',force=>true);' cmd from (select distinct object_name from test_tabs) t;