On Tue, Mar 18, 2008 at 9:58 AM, Chris Kratz <chris.kratz@vistashare.com> wrote:
> Y, turning nested loops off in specific cases has increased performance
> greatly. It didn't fix the planner mis-estimation, just the plan it chose.
> It's certainly not a panacea, but it's something we now try early on when
> trying to speed up a query that matches these characteristics.
I have to admit I've had one or two reporting queries in the past that
turning off nested_loop was the only reasonable fix due to
misestimation. I'd tried changing the stats targets etc and nothing
really worked reliably to prevent the nested_loop from showing up in
the wrong places.