Re: index vs. seq scan choice?

George Pavlov wrote:
>> From: Joshua D. Drake [mailto:jd(at)commandprompt(dot)com]
>>
>> In those rare cases wouldn't it make more sense to just set
>> enable_seqscan to off; run query; set enable_seqscan to on;
>
> 1. these cases are not that rare (to me);

I find that surprising.

>
> 2. setting enable_seqscan (in JDBC, say) from the application makes the
> whole thing quite a mess (need to do a batch of statements: each query
> wrapped in its enable/disable seq scan?) -- ideally, one would like to
> issue mostly SQL statements, not config parameters from the application;

Uh no. You do it at the beginning of the transaction, run your queries
then reset it right before (or after) commit.

>
> 3. if this is the recommended suggestion on how to run queries then why
> don't we just add HINTS to the system and be done with it...

I suggest you read the archives, twice, before suggesting hints.

>
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>
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