Re: How to find random records in a subset?

Try using a temporary table. It should be pretty fast. You'd do something like 1. Select from table1 according to search criteria 2. Insert data from #1 into temp_table1 3. Random selection from temp_table1 kgt Brian Dunning wrote:

I am using a routine to find 50 random records in a large MySQL database (about a million records) where I generate a list of 50 random unique ID's, and then use MySQL's "in" command to find them. I can't use "order by rand()" due to its performance hit. But I have to take it one more step: I want to first limit my found set to those matching a different search criteria, and then find 50 of those. Anyone? Can this be done all within MySQL, or is it going to require some humongo PHP arrays?