Re: get_actual_variable_range vs idx_scan/idx_tup_fetch

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От Marko Tiikkaja
Тема Re: get_actual_variable_range vs idx_scan/idx_tup_fetch
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Msg-id 54419D12.6030501@joh.to
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Ответ на Re: get_actual_variable_range vs idx_scan/idx_tup_fetch  (Tom Lane <tgl@sss.pgh.pa.us>)
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On 10/18/14, 12:15 AM, Tom Lane wrote:
> Marko Tiikkaja <marko@joh.to> writes:
>> I think there's a big difference between "this index was used to look up
>> stuff for planning" and "this index was used to answer queries quickly".
>
> I think that's utter nonsense.

Well you probably know a bit more about the optimizer than I do.  But I 
can't see a case where the stats provided by the index would be useful 
for choosing between two (or more) plans that don't use the index in the 
actual query.  If you're saying that there are such cases, then clearly 
I don't know something, and my thinking is in the wrong here.


.marko



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