On 12/13/2012 05:12 PM, AI Rumman wrote:
Why does the number of rows are different in actual and estimated?
Isn't that in the nature of estimates? An estimate is a heuristic guess at the number of rows it will find for the given query or part of a query. It's not uncommon for estimates to be out by several orders of magnitude. Guaranteeing estimates within bounded accuracy and in a given short amount of time (you don't want your planning time to overwhelm your execution time) isn't possible.
cheers andrew -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
