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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marco Di Cesare <Marco.DiCesare@pointclickcare.com>
cc: Merlin Moncure <mmoncure@gmail.com>,
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Subject: Re: Query with large number of joins
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Comments: In-reply-to Marco Di Cesare <Marco.DiCesare@pointclickcare.com>
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Date: Tue, 21 Oct 2014 12:50:32 -0400
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Marco Di Cesare <Marco.DiCesare@pointclickcare.com> writes:
>                 COUNT(DISTINCT "foxtrot_india"."bravo_romeo")  

Ah.  That explains why the planner doesn't want to use a hash aggregation
step --- DISTINCT aggregates aren't supported with those.

			regards, tom lane


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