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From "Francois Orsini" <francois.ors...@gmail.com>
Subject Re: SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE and reindexing
Date Wed, 07 Nov 2007 00:44:28 GMT
I believe a full table scan updates the internal row count for that table
but will not cause index cardinality (additional info) to be updated for
each index on that table...

http://db.apache.org/derby/docs/10.3/tuning/ctunstats848901.html
http://db.apache.org/derby/docs/dev/tuning/tuning-single.html#ctunstats46438

On Nov 6, 2007 4:13 PM, Stanley Bradbury <Stan.Bradbury@gmail.com> wrote:

> Dan Karp wrote:
> > I think we may be getting hit with DERBY-269 (stale index cardinality
> causes table scans).  The command listed in that JIRA ("alter table
> <table-name> compress [sequential]") isn't valid.  Calling
> SYSCS_UTIL.SYSCS_COMPRESS_TABLE works, but takes a huge amount of CPU, disk
> I/O, and disk space.  Is there a simpler, straightforward way to force
> recalculation of these indexes?
> >
> > https://issues.apache.org/jira/browse/DERBY-269
> >
> >
> According to the documentation: Cardinality statistics are updated when
> a table scan is performed so a " select * from <table> " should do it.
>
>
>

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