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

Below query can be used to delete all the duplicate except the one row with lowest "id" field value

DELETE t1 FROM table_name t1, table_name t2 WHERE t1.id > t2.id AND t1.name = t2.name

In the similar way, we can keep the row with the highest value in 'id' as follows

 DELETE t1 FROM table_name t1, table_name t2 WHERE t1.id < t2.id AND t1.name = t2.name