>>>>> "Tom" == Tom Mercha <mercha_t@xxxxxxxxxxx> writes: Tom> Hi All Tom> As we know, a query goes through number of stages before it is Tom> executed. One of these stages is query optimization (QO). That's not really true at all. One of the stages is query _planning_, which takes the (rewritten) query as input and converts it to something that the executor can take action on. There isn't actually any separate "optimization" phase. -- Andrew (irc:RhodiumToad)