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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,

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