How to remove duplicate entries from a mysql db?

Question

I have a table with some ids + titles. I want to make the title column unique, but it has over 600k records already, some of which are duplicates (sometimes several dozen ti

Answer 1

The solution posted by Nitin seems to be the most elegant / logical one.

However it has one issue:

ERROR 1093 (HY000): You can't specify target table 'student' for update in FROM clause

This can however be resolved by using (SELECT * FROM student) instead of student:

DELETE FROM student WHERE id IN (
SELECT distinct(s1.`student_id`) FROM (SELECT * FROM student) AS s1 INNER JOIN (SELECT * FROM student) AS s2
WHERE s1.`sex` = s2.`sex` AND
s1.`student_id` > s2.`student_id` AND
s1.`sex` = 'M'
ORDER BY `s1`.`student_id` ASC
)

Give your +1's to Nitin for coming up with the original solution.