Tom, Merlin, > It's not fundamentally different from single-column indexes. The only > aspect of a btree index that requires any knowledge about the content of > index entries is the "compare two index entries for lesser, equal, or > greater" operation. For that, we just compare the first columns, then > compare the second columns if the first are equal, etc. Plain > lexicographic sort semantics.
So the different columns of the index don't have seperate data pages? It's just a partitioned index node? Wow, no wonder I couldn't figure it out, I was looking for something more complicated ... BTW, while we're on the optimizer, what is random_page_cost supposed to represent, exactly? I used to think it was the ratio of index page retreivals to direct page retrievals, but I see that that's already being calculated for. I'm wondering if it might be possible to calculate RPC and eliminate it as a GUC. -- --Josh Josh Berkus Aglio Database Solutions San Francisco ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly