Ühel kenal päeval, L, 2005-12-03 kell 09:21, kirjutas Simon Riggs: > First off, I think we need to do some more work on partitioning so that > some knowledge about the union set is understood by the optimizer. At > the moment there is no concept of partition key, so its hard to spot > when two union sets have the same key to allow pushdown.
One of the easier cases would be non-overlapping (exclusive) constraints on union subtables on the joined column. This could serve as a "partition key", or in case of many nonoverlapping columns (ex.: table is partitioned by date and region), as many partition keys. ------------- Hannu ---------------------------(end of broadcast)--------------------------- TIP 1: 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