Stale Statistics Operations

-- PURPOSE: CHECK_STALE_STATS.SQL
-- This script is an automated way to deal with stale statistics operations that are
-- required to be done as part of manual upgrade OR when reported by DBUA.
--
-- This script will work in both Windows and Unix platforms from database
-- version 9.2 or higher.
-- ------------------------------------------------------------------------
-- DISCLAIMER:
-- This script is provided for educational purposes only. It is NOT
-- supported by Oracle World Wide Technical Support.
-- The script has been tested and appears to work as intended.
-- You should always run new scripts on a test instance initially.
-- ------------------------------------------------------------------------
--
SET FEEDBACK OFF
SET LINESIZE 250
SET SERVEROUTPUT ON

DECLARE
-- Variables declared
P_OTAB DBMS_STATS.OBJECTTAB;
MCOUNT NUMBER := 0;
P_VERSION VARCHAR2(10);
-- Cursor defined
CURSOR c1
IS
SELECT distinct schema
FROM dba_registry
ORDER by 1;

-- Beginning of the anonymous block
BEGIN
-- Verifying version from v$instance
SELECT version INTO p_version FROM v$instance;
DBMS_OUTPUT.PUT_LINE(chr(13));
-- Defining Loop 1 for listing schema which have stale stats
FOR x in c1
LOOP
DBMS_STATS.GATHER_SCHEMA_STATS(OWNNAME=>x.schema,OPTIONS=>'LIST AUTO',OBJLIST=>p_otab);

-- Defining Loop 2 to find number of objects containing stale stats
FOR i in 1 .. p_otab.count
LOOP
IF p_otab(i).objname NOT LIKE 'SYS_%'
AND p_otab(i).objname NOT IN ('CLU$','COL_USAGE$','FET$','INDPART$',
'MON_MODS$','TABPART$','HISTGRM$',
'MON_MODS_ALL$',
'HIST_HEAD$','IN $','TAB$',
'WRI$_OPTSTAT_OPR','PUIU$DATA',
'XDB$NLOCKS_CHILD_NAME_IDX',
'XDB$NLOCKS_PARENT_OID_IDX',
'XDB$NLOCKS_RAW OKEN_IDX', 'XDB$SCHEMA_URL',
'XDBHI_IDX', 'XDB_PK_H_LINK')
THEN
-- Incrementing count for each object found with statle stats
mcount := mcount + 1;
END IF;
-- End of Loop 2
END LOOP;

-- Displays no stale statistics, if coun is 0
IF mcount!=0
THEN
-- Displays Schema with stale stats if count is greater than 0
DBMS_OUTPUT.PUT_LINE('-------------------------------------------------------------------------------------------------------');
DBMS_OUTPUT.PUT_LINE('-- ' x.schema ' schema contains stale statistics use the following to gather the statistics ''--');
DBMS_OUTPUT.PUT_LINE('-------------------------------------------------------------------------------------------------------');
--DBMS_OUTPUT.PUT_LINE('');

-- Displays Command to be executed if schema with stale statistics is found depending on the version.
IF SUBSTR(p_version,1,5) in ('8.1.7','9.0.1','9.2.0')
THEN
DBMS_OUTPUT.PUT_LINE(chr(13));
DBMS_OUTPUT.PUT_LINE('EXEC DBMS_STATS.GATHER_SCHEMA_STATS('''x.schema''',OPTIONS=>''''GATHER'''', ESTIMATE_PERCENT => DBMS_STATS.AUTO_SAMPLE_SIZE, METHOD_OPT => ''''FOR ALL COLUMNS SIZE AUTO'''', CASCADE => TRUE);');
ELSIF SUBSTR(p_version,1,6) in ('10.1.0','10.2.0','11.1.0')
THEN
DBMS_OUTPUT.PUT_LINE(chr(13));
DBMS_OUTPUT.PUT_LINE('EXEC DBMS_STATS.GATHER_DICTIONARY_STATS('''x.schema''',OPTIONS=>''''GATHER'''', ESTIMATE_PERCENT => DBMS_STATS.AUTO_SAMPLE_SIZE, METHOD_OPT => ''''FOR ALL COLUMNS SIZE AUTO'''', CASCADE => TRUE);');
ELSE
DBMS_OUTPUT.PUT_LINE(chr(13));
DBMS_OUTPUT.PUT_LINE('Version is 'p_version);
END IF;
ELSE
DBMS_OUTPUT.PUT_LINE('-- There are no stale statistics in ' x.schema ' schema.');
DBMS_OUTPUT.PUT_LINE(chr(13));
END IF;
-- Reset count to 0.
mcount := 0;
-- End of Loop 1
END LOOP;
END;
/

SET FEEDBACK ON
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