> ... or plan the query with the actual parameter value you get, and also
> record the range of the parameter values you expect the plan to be valid
> for. If at execution time the parameter happens to be out of that range,
> replan, and possibly add new sublpan covering the extra range. This
> could still work with prepared queries (where you don't get any
> parameter values to start with) by estimating the most probable
> parameter range (whatever that could mean), and planning for that.
Another thought: if the cached plans get their own table (as it was
suggested) then you could also start gathering parameter range
statistics meaningfully... and on the next replan you know what to
optimize your planning efforts for.
Cheers,
Csaba.