Re: Window Functions with identical PARTITION BY and ORDER BY clauses evaluated separately - Mailing list pgsql-bugs

From David G. Johnston
Subject Re: Window Functions with identical PARTITION BY and ORDER BY clauses evaluated separately
Date
Msg-id CAKFQuwYKrE538QskTWa+_eznnKTFkNhRfnLW_H5OuNW4xgX1hQ@mail.gmail.com
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In response to Re: Window Functions with identical PARTITION BY and ORDER BY clauses evaluated separately  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Window Functions with identical PARTITION BY and ORDER BY clauses evaluated separately
List pgsql-bugs
On Sun, Mar 9, 2025 at 10:27 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Sat, Mar 8, 2025 at 12:50 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> For a shorter fix
>> When multiple window functions are used, all the window functions
>> having syntactically equivalent PARTITION BY and ORDER BY clauses
>> in their window definitions are guaranteed to see the same
>> ordering of the input rows, even if the ORDER BY does not uniquely
>> determine the ordering.
 
 So let's go with
my wording less the "syntactically".


+1

David J.

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