Last time indexes were rebuilt

Hi,

 I will like to know when was the last time indexes were rebuilt.  

 I am using this query  select distinct (LAST_ddL_TIME) as last  from dba_objects, but DDL could mean some else besides rebuild for indexes ?

 There is some automatic way to keep the indexes rebuild up to date automatically  ?
LVL 1
joe_echavarriaDatabase AdministratorAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

johnsoneSenior Oracle DBACommented:
If you use DROP and CREATE on the indexes to rebuild them, then the CREATED column in DBA_OBJECTS should show you  the last time it was rebuilt.  If you use ALTER INDEX...REBUILD, then there isn't a column that I am aware of that would tell you the last time it was rebuilt.

The bigger question is why do you need to rebuild the indexes?  Typically indexes would only be rebuilt if a massive delete has taken place.
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Guy Hengel [angelIII / a3]Billing EngineerCommented:
the last_ddl could be when the index was marked unusable/usable etc, so not necessarily when it was rebuild

anyhow, the "last time" it was done is not really the key (unless you want to avoid rebuilding it all day long....)
in which case last_ddl_time still is useful

refer to this page to review some considerations about rebuilding indexes
http://www.dba-oracle.com/art_index1.htm
0
awking00Information Technology SpecialistCommented:
If you rebuild your indexes using "ALTER INDEX yourindex REBUILD COMPUTE STATISTICS", you can issue the following query to determine when the index was rebuilt:
select last_analyzed from dba_indexes where index_name = 'YOURINDEX';

You might also create a procedure to automate this somewhat -
create or replace procedure rebuild_idx (varchar2 in idxname) is
v_sql varchar2(255);
v_lastanal date;
begin
select last_analyzed into v_lastanal from user_indexes where index_name = upper(idxname);
if v_lastanal < sysdate - 2 --in this example more than two days ago but you pick the timeframe
then
v_sql := 'alter index '||idxname||' rebuild compute statistics';
execute immediate v_sql;
end if;
end;
/
0
johnsoneSenior Oracle DBACommented:
LAST_ANALYZED would work only if that is the only way you gather statistics.  If you gather statistics another way outside that command (i.e. DBMS_STATS), then that column wouldn't be accurate.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Oracle Database

From novice to tech pro — start learning today.