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From Rick Hillegas <rick.hille...@oracle.com>
Subject Re: Log indexes used by queries
Date Tue, 26 Mar 2013 13:29:45 GMT
On 3/22/13 12:44 PM, mvarvil wrote:
> What class/method could you point me to such that I could log the index
> selected and used by the optimizer?  (I might be overreaching, as perhaps
> there isnt a single class that I can modify)
>
> *My objective* is to identify useless and extraneous indexes in the
> database.   I would like to capture a list of indexes used by the database
> while it is in use by an application over a period of time.   Comparing the
> list against ALL the indexes created in the system should provide a starting
> point for identifying extraneous indexes.
>
> Alternatively, perhaps one might recommend enabling a logger class that
> outputs this information already.
>
> Enabling logQueryPlan is my least favorite idea, because of its verbosity.
> I'm open to other ideas too.
>
> Thanks.
> Mark
>
>
>
> --
> View this message in context: http://apache-database.10148.n7.nabble.com/Log-indexes-used-by-queries-tp128323.html
> Sent from the Apache Derby Developers mailing list archive at Nabble.com.
>
Hi Mark,

Another approach to this problem might be to instrument the constructor 
of TableScanResultSet so that it records what conglomerates are actually 
opened for scanning at execution time.

Hope this helps,
-Rick

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