Simon Riggs <[EMAIL PROTECTED]> writes: > I meant use the same sampling approach as I was proposing for ANALYZE, > but do this at plan time for the query. That way we can apply the > function directly to the sampled rows and estimate selectivity.
I think this is so unlikely to be a win as to not even be worth spending any time discussing. The extra planning time across all queries will vastly outweigh the occasional improvement in plan choice for some queries. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match