You need to regularly run 'analyze'.
Chris
Richard van den Berg wrote:
> Hi there,
>
> I am quite new to postgresql, and love the explain feature. It enables
> us to predict which SQL queries needs to be optimized before we see any
> problems. However, I've run into an issue where explain tells us a the
> costs of a quiry are tremendous (105849017586), but the query actually
> runs quite fast. Even "explain analyze" shows these costs.
>
> This makes me wonder: can the estimates explain shows be dead wrong?
>
> I can explain in more detail (including the query and output of explain)
> if needed. I'm using 7.4 on Solaris 8.
>
> Sincerely,
>