RE: Learning more about and reading 10053 trace files

Hi Charles - I just read your post quickly and I'm not sure about this, but it sounds to me like maybe there is no "First K" rows calculation for the DISTINCT query because anytime you have a DISTINCT, GROUP BY, ORDER BY or other clause that forces all the data to be fetched and sorted prior to being returned to the user, it makes it impossible to do any type of "FIRST ROWS" processing - because you can't just grab the first 1, 10, or 100 rows until you grab them all and process them as requested, so it makes sense that the CBO wouldn't even consider the cost for such an access method.  

Regards,
Brandon

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