Re: Database Reorg

Chuck Isaacson (ccisaac_at_mtu.edu) wrote:
: Very simply put, you should reorg: a) if performance is degrading and
: there is nothing else to blame, or b) if you are running out of contiguous
: space for new objects but you have sufficient total free space available.
 

: Chuck

Good point. Sometimes trying to compress single tables only causes more extents than in the beginning. That is althought with large tables.

If you want to compress tablespaces you should compress all tables, not just those with many extents.

Export/import will change the initial extent size and try to reserve more continuous space than the original table. That means table may be 100MB large with 40 extents. If you export the table, drop table and try to import it again, import will try to reserve 100MB continuous space for the table. Usually TS won't have that large empty hole in the data file, unless you create another datafile for your table.

Of course you can change the initial data size, but you will certainly have extents count increasing...

• Harri --

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  Harri Kaukovuo, University of Jyvaskyla, hkau_at_jyu.fi

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