No more must you think about how to find a clean way to delete duplicate records in your database table.  The following article will provide a single SQL query that will delete rows that are duplicated in your table.  Before you begin, be sure you've tracked down the bad code that is causing this; otherwise, you will need to run it multiple times!

This is a must read for beginning developers in understanding how to index your database tables and more importantly, why you must index your database.

Whenever you need to display "random" data, it is always so tempting to take the simplest solution, e.g. SELECT * FROM mytable ORDER BY RAND().  This of course works perfectly; however, if your database table contains a lot of records (10,000+) a query like this can take seconds to complete – instead of 1/10^th of a second.  With a bit of extra effort and careful thought, this process can be improved and still provide truly random results.