Re: Terrible performance on wide selects - Mailing list pgsql-general

From Tom Lane
Subject Re: Terrible performance on wide selects
Date
Msg-id 19506.1042844812@sss.pgh.pa.us
Whole thread Raw
In response to Terrible performance on wide selects  (Steve Crawford <scrawford@pinpointresearch.com>)
List pgsql-general
Steve Crawford <scrawford@pinpointresearch.com> writes:
> So the question is, does it seem reasonable that a query on fundamentally
> identical data should take 70-90 times as long when displayed as individual
> columns vs. when output as a raw array and, more imporantly, what can I do to
> get acceptable performance on this query?

There are undoubtedly some places that are O(N^2) in the number of
targetlist items.  Feel free to do some profiling to identify them.
It probably won't be real hard to fix 'em once identified.

            regards, tom lane

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