IF you have a version of MySQL that is recent enough (4.0+) you can merge your two queries *when you run them* by using the UNION predicate.
http://dev.mysql.com/doc/mysql/en/UNION.html Much better than a client-side merge. Shawn Green Database Administrator Unimin Corporation - Spruce Pine "David Turner" <[EMAIL PROTECTED]> wrote on 10/04/2004 05:17:12 PM: > Thanks for the suggestions over the weekend! I will be looking in to > this in a few days - for now I think I am just going to have to re-write > my PHP script to make 2 separate queries and array_merge() them - which > invariably seems to solve "OR" problems. But there should be a better > way, no? > > -Dave > > -----Original Message----- > From: David Turner [mailto:[EMAIL PROTECTED] > Sent: October 1, 2004 4:04 PM > To: [EMAIL PROTECTED] > Subject: Indexing for OR clauses > > > > Wondering if anyone can give me advice on indexing for OR clauses. > > I have a table with a number of fields, two of which are sender_id and > receiver_id. I also have a query such as this: > > SELECT ... > WHERE (sender_id = 98765 OR reciever_id = 98765) > > The query is OK for a limit of 10, but if I increase that to 25, it > becomes inordinately slower (it is a large table). > > Is it better for me to have two separate indexes, one for each of > sender_id and receiver_id, or one index with both sender_id and > receiver_id? Or should I just avoid the use of OR? Or am I simply > missing something? > > -Dave > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] >
