Howdy all, I've got a question regarding optimizing a query.
I've got two tables: listing and listing_city_xref listing is a pretty wide table with many fields that can be queried by users. There is a subset of fields that are always in queries of this table but there are many additional fields that may or maynot be included. The primary key consists of two fields, group_id int and listing_id varchar(30). The listing_city_xref table is very simple. It consists of 3 fields: group_id, listing_id, city_id. All three fields form the PK. There is an index on group_id and listing_id as well as a foreign key that points back to the listing table consisting of these two fields. I created an index on the listing table that contains the group_id, listing_id, and the other fields that all searches use. When I run a query that joins the two tables on the group_id and listing_id and I search only fields that are included in the index that I mentioned the query is really fast. If I add another field that's not included in the index the query slows down by a factor of 100. I can't simply index every field in the listing table so what can I do? I don't understand why added extra critieria to the query destroys its performance. Any ideas? Thanks, Tripp __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
