I have several times now run into what seems like similar performance problems with some of my postgresql queries.
I have a view that runs reasonably quicky. I use this view in a subselect in another query and that query too runs reasonably quicky. The view returns some unwanted duplicate rows so I modify it using either DISTINCT or GROUP BY to eliminate them. View still runs reasonably quickly. I use the modified view as a subselect as above, but now the query runs 2-3 orders of magnitude more slowly than before. Before I go through the effort of putting together a specific and concise test case, has anyone seen this general pattern and have an explanation or advice? (PG-8.2.3) ---------------------------(end of broadcast)--------------------------- TIP 7: You can help support the PostgreSQL project by donating at http://www.postgresql.org/about/donate