George Pavlov wrote:
From: Tom Lane
"George Pavlov" <gpavlov@xxxxxxxxxxxxxx> writes:
From: Joshua D. Drake [mailto:jd@xxxxxxxxxxxxxxxxx]
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);
It strikes me that you probably need to adjust the planner cost
parameters to reflect reality on your system. Usually dropping
random_page_cost is the way to bias the thing more in favor of
index scans.
Thanks, Tom, I will try that. Seems better than fiddling with
enable_seqscan around every query/transaction.
Joshua, I fail to understand why setting and unsetting enable_seqscan on
a per query/transaction basis is in any way preferable to query hints?
Don't get me wrong, I don't like the idea of hints, and I have read the
archives on the subject and I agree with the philosophy, but if the
optimization toolkit for routine application queries is going to include
setting config parameters that just smacks of hints by another name...
I actually have zero opinion on hints, my comment was more about opening
the wasps nest of the hints discussion more than anything :)
Joshua D. Drake
George
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