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From Mike Matrigali <mikem_...@sbcglobal.net>
Subject Re: DB File Size
Date Tue, 20 Jun 2006 17:19:16 GMT
Any chance you can post the test.  If not can you describe the test
a little more:
o number of tables (ie. is it only one?)
o what is the ddl
o what is the expected life of a row and the distribut
o what version are you using?

I added some work to do better automatic space reclamation of blob/clobs
in the trunk awhile back.

Otherwise deleted space is automatically reclaimed after (in the case of 
non blob/clob):
1) the deleted row transaction commits
2) all rows on a page are deleted.

Note that space is never automatically returned to the OS, only 
automatically made available for future inserts.  So worst case is
do all the inserts first and then do the deletes (but that does not
sound like what your test does.)

LEE YAN SHEN, ITDO wrote:
> Hi,
> 
> I have been doing stress test on the database doing lots of 
> insert/update/delete/query rapidly and found that one of the files is 
> growing rapidly although the number of records in the db remain more or 
> less constant during the test. In fact, it grew 100 over megabytes after 
> about 350,000 transactions. The only way to reduce the file size was to 
> do a compress table which made it reduce to only 2 MB.
> 
> Is it the expected behaviour? From the documentation, derby should be 
> zero admin and be able to reuse space made available after a record is 
> deleted. Hence I do not expect the file size to grow constantly with the 
> same number of records.
> 
> Can anyone advise please?
> 
> Thanks.
> 
> 
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