ORACLE Undo Advisor

分类： Oracle

General Information
Purpose	Undo advisor gives users recommendation on setting undo retention and sizing undo tablespace. Undo retention is in seconds.
Source	{ORACLE_HOME}/rdbms/admin/dbmsuadv.sql
First Available	10.1
Data Type	CREATE OR REPLACE TYPE dbms_uadv_arr as VARRAY(100) of NUMBER; /
Dependencies	DBA_TABLESPACES DBMS_UNDO_ADV PRVT_ADVISOR DBMS_SQL GV$DATABASE UTL_LMS DBMS_SYS_ERROR GV$PARAMETER X$KSPPCV2 DBMS_UADV_ARR GV$ROLLSTAT X$KSPPI DBMS_UNDOADV_LIB PLITBLM
Overload Definitions	Overload 1 Subprogram is based on historical information in memory or in SWRF from start time to end time Overload 2 Subprogram is based on historical information in memory or in SWRF from sysdate-7 to sysdate Overload 3 Subprogram is based on historical information in SWRF from snapid s1 to snapid s2 (AWR)
Security Model	execute is granted to the DBA role
BEST_POSSIBLE_RETENTION
Returns the best possible undo retention current undo tablespace can support based on undo stats between the start time and end time Overload 1	dbms_undo_adv.best_possible_retention( starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	SELECT dbms_undo_adv.best_possible_retention(SYSDATE-1/24, SYSDATE) FROM dual;
Overload 2	dbms_undo_adv.best_possible_retention RETURN NUMBER;
	SELECT dbms_undo_adv.best_possible_retention FROM dual;
Overload 3	dbms_undo_adv.best_possible_retention(s1 IN NUMBER, s2 IN NUMBER) RETURN NUMBER;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; SELECT dbms_undo_adv.best_possible_retention(578, 600) FROM dual;
LONGEST_QUERY
Returns the length of the longest query (between the start time and the end time) Overload 1	dbms_undo_adv.longest_query(starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	SELECT dbms_undo_adv.longest_query(SYSDATE-1/24, SYSDATE) FROM dual;
Overload 2	dbms_undo_adv.longest_query RETURN NUMBER;
	SELECT dbms_undo_adv.longest_query FROM dual;
Overload 3	dbms_undo_adv.longest_query(s1 IN NUMBER, s2 IN NUMBER) RETURN NUMBER;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; SELECT dbms_undo_adv.longest_query(578, 600) FROM dual;
RBU_MIGRATION
Undocumented Overload 1	dbms_undo_adv.rbu_migration(starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	SELECT dbms_undo_adv.rbu_migration(SYSDATE-1/24, SYSDATE) FROM dual;
Overload 2	dbms_undo_adv.rbu_migration RETURN NUMBER;
	SELECT dbms_undo_adv.rbu_migration FROM dual;
REQUIRED_RETENTION
Returns the required undo retention to support longest query based on undo stats between the start time and the end time Overload 1	dbms_undo_adv.required_retention(starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	SELECT dbms_undo_adv.required_retention(SYSDATE-30, SYSDATE) FROM dual; SELECT dbms_undo_adv.required_retention(SYSDATE-1/1440, SYSDATE) FROM dual;
Overload 2	dbms_undo_adv.required_retention RETURN NUMBER;
	SELECT dbms_undo_adv.required_retentionFROM dual;
Overload 3	dbms_undo_adv.required_retention(s1 IN NUMBER, s2 IN NUMBER) RETURN NUMBER;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; SELECT dbms_undo_adv.required_retention(578, 600) FROM dual;
REQUIRED_UNDO_SIZE
Returns the required undo tablespace size to support undo retention based on undo stats between the start time and the end time Overload 1	dbms_undo_adv.required_undo_size(retention IN NUMBER,  starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	SELECT dbms_undo_adv.required_undo_size(900, SYSDATE-30, SYSDATE) FROM dual;
Overload 2	dbms_undo_adv.required_undo_size(retention IN NUMBER) RETURN NUMBER;
	SELECT dbms_undo_adv.required_undo_size(20) FROM dual; SELECT dbms_undo_adv.required_undo_size(1440) FROM dual;
Overload 3	dbms_undo_adv.required_undo_size(retention IN NUMBER, s1 IN NUMBER,  s2 IN NUMBER) RETURN NUMBER;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; SELECT dbms_undo_adv.required_undo_size(1440, 578, 600) FROM dual;
Overload 4	dbms_undo_adv.required_undo_size( retention IN dbms_uadv_arr, utbsize IN OUT dbms_uadv_arr, starttime IN DATE, endtime IN DATE) RETURN NUMBER;
	TBD
Overload 5	dbms_undo_adv.required_undo_size( retention IN dbms_uadv_arr, utbsize IN OUT dbms_uadv_arr) RETURN NUMBER;
	TBD
Overload 6	dbms_undo_adv.required_undo_size( retention IN dbms_uadv_arr, utbsize IN OUT dbms_uadv_arr, s1 IN NUMBER, s2 IN NUMBER) RETURN NUMBER;
	TBD
UNDO_ADVISOR
Uses the advisor framework to identify problems and provide recommendations Overload 1	dbms_undo_adv.undo_advisor( starttime IN DATE, endtime IN DATE, instance IN NUMBER)  RETURN VARCHAR2;
	set serveroutput on DECLARE v VARCHAR2(300);  BEGIN v := dbms_undo_adv.undo_advisor(SYSDATE-1/1440, SYSDATE, 1); dbms_output.put_line(v); END; /
Overload 2	dbms_undo_adv.undo_advisor(instance IN NUMBER) RETURN VARCHAR2;
	set serveroutput on DECLARE v VARCHAR2(100); BEGIN v := dbms_undo_adv.undo_advisor(1); dbms_output.put_line(v); END; /
Overload 3	dbms_undo_adv.undo_advisor(s1 IN NUMBER, s2 IN NUMBER, instance IN NUMBER) RETURN VARCHAR2;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; set serveroutput on DECLARE retval VARCHAR2(200); BEGIN  retval := dbms_undo_adv.undo_advisor(578, 600, 1); dbms_output.put_line(retval); END; /
UNDO_AUTOTUNE
Undocumented	dbms_undo_adv.undo_autotune(autotune_enabled OUT BOOLEAN) RETURN BOOLEAN;
	DECLARE bp BOOLEAN; br BOOLEAN; BEGIN br := dbms_undo_adv.undo_autotune(bp); IF bp THEN dbms_output.put_line('Parameter is true'); ELSE dbms_output.put_line('Parameter is false'); END IF; IF br THEN dbms_output.put_line('Return value is true'); ELSE dbms_output.put_line('Return value is false'); END IF; END; /
UNDO_HEALTH
Find out the problem in undo tablespace and provide recommendation to fix the problem. If no problem found, return value is 0 Overload 1	dbms_undo_adv.undo_health( problem OUT VARCHAR2, recommendation OUT VARCHAR2, rationale OUT VARCHAR2, retention OUT NUMBER, utbsize OUT NUMBER) RETURN NUMBER;
	set serveroutput on DECLARE prob VARCHAR2(100); reco VARCHAR2(100); rtnl VARCHAR2(100); retn PLS_INTEGER; utbs PLS_INTEGER; retv PLS_INTEGER; BEGIN retv := dbms_undo_adv.undo_health(prob, reco, rtnl, retn, utbs); dbms_output.put_line('Problem: ' || prob); dbms_output.put_line('Recmmnd: ' || reco); dbms_output.put_line('Rationl: ' || rtnl); dbms_output.put_line('Retentn: ' || TO_CHAR(retn)); dbms_output.put_line('UTBSize: ' || TO_CHAR(utbs)); END; /
Overload 2	dbms_undo_adv.undo_health( starttime IN DATE, endtime IN DATE, problem OUT VARCHAR2, recommendation OUT VARCHAR2, rationale OUT VARCHAR2, retention OUT NUMBER, utbsize OUT NUMBER) RETURN NUMBER;
	set serveroutput on DECLARE prob VARCHAR2(100); reco VARCHAR2(100); rtnl VARCHAR2(100); retn PLS_INTEGER; utbs PLS_INTEGER; retv PLS_INTEGER; BEGIN retv := dbms_undo_adv.undo_health(SYSDATE-1/24, SYSDATE, prob, reco, rtnl, retn, utbs); dbms_output.put_line('Problem: ' || prob); dbms_output.put_line('Recmmnd: ' || reco); dbms_output.put_line('Rationl: ' || rtnl); dbms_output.put_line('Retentn: ' || TO_CHAR(retn)); dbms_output.put_line('UTBSize: ' || TO_CHAR(utbs)); END; /
Overload 3	dbms_undo_adv.undo_health( s1 IN NUMBER, s2 IN NUMBER, problem OUT VARCHAR2, recommendation OUT VARCHAR2, rationale OUT VARCHAR2, retention OUT NUMBER, utbsize OUT NUMBER) RETURN NUMBER;
	col instart_fmt noprint; col inst_name format a12 heading 'Instance'; col db_name format a12 heading 'DB Name'; col snap_id format 99999990 heading 'Snap Id'; col snapdat format a18 heading 'Snap Started' just c; col lvl format 99 heading 'Snap|Level'; set heading on; break on inst_name on db_name on host on instart_fmt skip 1; ttitle off; SELECT TO_CHAR(s.startup_time,' DD MON "at" HH24:MI:SS') INSTART_FMT, di.instance_name INST_NAME, di.db_name DB_NAME, s.snap_id SNAP_ID, TO_CHAR(s.end_interval_time,'DD MON YYYY HH24:MI') SNAPDAT, s.snap_level LVL FROM dba_hist_snapshot s, dba_hist_database_instance di WHERE di.dbid = s.dbid AND di.instance_number = s.instance_number AND di.startup_time = s.startup_time ORDER BY snap_id; DECLARE prob VARCHAR2(100); reco VARCHAR2(100); rtnl VARCHAR2(100); retn PLS_INTEGER; utbs PLS_INTEGER; retv PLS_INTEGER; BEGIN retv := dbms_undo_adv.undo_health(578, 600, prob, reco, rtnl, retn, utbs); dbms_output.put_line('Problem: ' || prob); dbms_output.put_line('Recmmnd: ' || reco); dbms_output.put_line('Rationl: ' || rtnl); dbms_output.put_line('Retentn: ' || TO_CHAR(retn)); dbms_output.put_line('UTBSize: ' || TO_CHAR(utbs)); END; /
UNDO_INFO
Returns current undo tablespace name, max possible size, if it is auto extensible, current undo retention value and if the undo tablespace has guaranteed undo retention	dbms_undo_adv.undo_info( table_space_name OUT VARCHAR2, table_space_size OUT NUMBER, auto_extend OUT BOOLEAN, undo_retention OUT NUMBER, retention_guarantee OUT BOOLEAN) RETURN BOOLEAN;
	set serveroutput on DECLARE tsn VARCHAR2(40); tss NUMBER(10); aex BOOLEAN; unr NUMBER(5); rgt BOOLEAN; retval BOOLEAN; BEGIN retval := dbms_undo_adv.undo_info(tsn, tss, aex, unr, rgt); dbms_output.put_line('Undo Tablespace Is: ' || tsn); dbms_output.put_line('Undo Tablespace Size Is: ' || TO_CHAR(tss)); IF aex THEN dbms_output.put_line('Undo Autoextend Is Set To: TRUE'); ELSE dbms_output.put_line('Undo Autoextend Is Set To: FALSE'); END IF; dbms_output.put_line('Undo Retention Is: ' || TO_CHAR(unr)); IF rgt THEN dbms_output.put_line('Undo Guarantee Is Set To: TRUE'); ELSE dbms_output.put_line('Undo Guarantee Is Set To: FALSE'); END IF; END; /

[@more@]