Why db2 reorg

REM If the schema is not supplied, all tables and indexes in the database are reorganized. Agreed, the whole purpose of DB2 is to run it on iSeries. To continue this discussion, please ask a new question. Get answers from your peers along with millions of IT pros who visit Spiceworks. BAT DB2 database name If i substitute the name of the database that needs the reorg in the database name portion of the command script is this all I need to do?

Best Answer. Verify your account to enable IT peers to see that you are a professional. Hopefully most of your pages are in Buffer Pool. Even if they are not they are often in smart disk cache. I cost to look an extent is not significant. I have never been particularly concerned about extents other than if a risk of blowing a limit.

Even in old days when Reorg was a bit slow, other types of Copy of pages could recombine Extents without doing Reorg sorts, index rebuilds, etc. Do we want to Reorg massive objects because in a lot of Extents?

Absolutely not. This was laughable stuff for me, all those years ago. Industry "best practice" ain't best practice at all. IBM told us: "Don't ask us how it works, tell us your problem and we will tell you how to solve it" What absolute bad advice! We really gotta try to understand what goes on and what really matters, and why. So we can do it right ourselves. Not easy of course. Above all, we want to understand when and why we Reorg, and not just follow some rules of thumb, which may apply sometimes, but not always.

If we don't measure performance, before and after Reorg, will we know if our strategy is right, or did we perhaps wait for too much degradation before we triggered the action? Search Options. Skip to main content Press Enter. Skip auxiliary navigation Press Enter. Contact Us. Quick Links. My Profile. My Contacts. My Networks. My Presentations. My Inbox. My Forums. My Communities. Getting Started. Make a Discussion Post.

Join a Community. Make a Connection. Explore Forums. Post Your First Message. Complete Profile. Skip main navigation Press Enter. However, I believe that partition reorgs are only classic offline at this point. Also, classic offline reorgs that do not cluster on an index use the least time. Need your help on this. Inplace reorgs greatly reduce the down time for a table. Option 2 is to range partition your table. I think you can then reorganize each partition individually. Thank you so much.

I will look into option 1 but it seems from my readings that option 2 you cannot do online reorgs In your experience is it unusual for a table of this size to take almost a day to inline reorg? It seems very wrong. I believe they added online reorgs for partitions in It is not unusual for reorg to take longer than 6 hours for large tables. It depends on the size of the table, not just the number of rows.

Are you reorging when a reorg is truly needed? Unfortunately we will not move to The problem is we are forbid from running outside window so jobs are often killed. Your email address will not be published. Notify me of follow-up comments by email. Notify me of new posts by email. This site uses Akismet to reduce spam. Learn how your comment data is processed.

Skip to content This is the first in a series of blog entries on reorgs. Document Actions. Consider the following factors, which might indicate that you should reorganize a table: A high volume of insert, update, and delete activity on tables accessed by queries.

If many rows are inserted, there may not be enough free space to keep them in the clustered sequence.

If many rows are deleted, the table will still have the space allocated and a REORG can free the unnecessary space. Significant changes in the performance of queries that use an index with a high cluster ratio.