Re: Why we don't want hints Was: Slow count(*) again...

Hi. I have the idea: hints joined to function. For example instead of

WHERE table1.field1=table2.field2
write:
WHERE specificeq(table1.field1,table2.field2)

and hints add to declaration of specificeq function.

2011/2/23, Robert Haas :
> On Wed, Feb 16, 2011 at 4:22 PM, Bruce Momjian  wrote:
>> I am not excited about the idea of putting these correlations in
>> queries.  What would be more intesting would be for analyze to build a
>> correlation coeffficent matrix showing how columns are correlated:
>>
>>        a   b   c
>>    a   1   .4  0
>>    b   .1  1   -.3
>>    c   .2  .3  1
>>
>> and those correlations could be used to weigh how the single-column
>> statistics should be combined.
>
> If you can make it work, I'll take it... it's (much) easier said than
> done, though.
>
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> Robert Haas
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> The Enterprise PostgreSQL Company
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pasman