On 6/23/17 09:54, Tom Lane wrote:
>> However, I can use same expression more than once in partition key.
>
> ... and so, I can't get excited about extending it to expressions.
> Where would you stop --- for example, are i and (i) equal? What
> about (i) and (case when true then i else j end)? In principle,
> the system could recognize both those identities, but it seems
> silly to expend code on it just for nagware purposes.
We also allow the same column more than once in an index. We probably
don't have to be more strict here.
--
Peter Eisentraut http://www.2ndQuadrant.com/
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