Portal | Manuals | References | Downloads | Info | Programs | JCLs | Master the Mainframes
IBM Mainframe Computers Forums Index
 
Register
 
IBM Mainframe Computers Forums Index Mainframe: Search IBM Mainframe Forum: FAQ Memberlist Usergroups Profile Log in to check your private messages Log in
 

 

Time taken by a DB2 Query increases

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> DB2
View previous topic :: :: View next topic  
Author Message
Geethi

New User


Joined: 03 Mar 2007
Posts: 10
Location: US

PostPosted: Tue Jul 03, 2007 2:37 am    Post subject: Time taken by a DB2 Query increases
Reply with quote

Hi,

I am having a SELECT statement with DISTINCT, GROUP BY, CASE clauses. This is used to create a report. But each time I run the query, the total time taken by it, is increased. Please somebody tell me why this happen so.

Thanks in advance,
Geethi
Back to top
View user's profile Send private message

dick scherrer

Site Director


Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Tue Jul 03, 2007 2:43 am    Post subject:
Reply with quote

Hello,

Please post your full query, the definition of the table(s) referenced, approximately how many rows are in each table, and the growth rate for the tables. Do the tables have purge criteria (i.e. are rows regularly deleted or will this continue to grow with no restraint)?

Did this suddenly happen or has the time been increasing over some period of time.
Back to top
View user's profile Send private message
Geethi

New User


Joined: 03 Mar 2007
Posts: 10
Location: US

PostPosted: Tue Jul 03, 2007 2:55 am    Post subject: Re: Time taken by a DB2 Query increases
Reply with quote

So far the query was taking less than 5 minutes of time. Suddenly it started taking 380 sec, 480 sec, 720 sec and so on.
Back to top
View user's profile Send private message
dick scherrer

Site Director


Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Tue Jul 03, 2007 3:46 am    Post subject:
Reply with quote

Hello,

Well, 5 min is 300 seconds, so it is not that big a jumo to 380. It sounds like the run time may increase exponentially rather than linear.

If you post the info requested earlier, we may be able to offer suggestions.
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> DB2 All times are GMT + 6 Hours
Page 1 of 1

 

Search our Forum:

Similar Topics
Topic Author Forum Replies Posted
No new posts Need DB2 query to fetch previous row ! Chandan1993 DB2 10 Sat Jun 03, 2017 10:43 am
No new posts DSNACCOX (can it be run on 1 db/ts, t... SRICOBSAS DB2 5 Sat May 06, 2017 12:59 am
No new posts LISTIDR compiled date/time jerryte IBM Tools 3 Thu Apr 20, 2017 7:37 pm
No new posts Application not run by time HH:MM tri... jzhardy IBM Tools 1 Sun Apr 09, 2017 3:22 pm
No new posts Date and time format in CICS Chandru3183 CICS 2 Sat Mar 18, 2017 12:46 pm


Facebook
Back to Top
 
Mainframe Wiki | Forum Rules | Bookmarks | Subscriptions | FAQ | Tutorials | Contact Us