Julius Stroffek <[EMAIL PROTECTED]> writes: > I rewrote a patch a bit.
This hook seems very strangely defined to me. Why did you not put the hook at the point where the current geqo-vs-regular decision is made? I do not see the value of duplicating the joinlist-expansion logic, which is what you're going to have to do if you use a hook that replaces make_rel_from_joinlist. The only things you could do differently than it does would be (1) be smarter about full outer joins, which was not part of the agenda that I heard of, or (2) willfully disregard the user's from_collapse_limit and join_collapse_limit settings, which doesn't seem like an amazingly good idea either. Also, "optimizer_hook" seems nearly content-free as a name for use in this area; I see no reason why the particular sub-section of the planner we're discussing here has more title to that name than other parts. Something like "join_order_search_hook" might be more appropriate. 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