Simon Riggs <simon(at)2ndquadrant(dot)com> writes:
> Say if cost of best plan >= N then recheck query for strangeness. If
> anything found, re-plan query.
Whatever makes you think that would be useful?
The usual result of undetected duplicate WHERE clauses is an
*underestimate* of runtime, not an overestimate (because it thinks
too few tuples will be selected).
regards, tom lane
In response to
pgsql-performance by date
|Next:||From: Tom Lane||Date: 2008-02-11 16:59:22|
|Subject: Re: Update with Subquery Performance |
|Previous:||From: Linux Guru||Date: 2008-02-11 11:06:44|
|Subject: Update with Subquery Performance|