Question

Consider the following table “tweets”

tweet_id  call_id   id_str  timestamp  text
--------------------------------------------------
1         11        12345   312323134  lorem ipsum
2         11        12345   312323134  lorem ipsum
3         11        12345   312323134  lorem ipsum
4         11        12345   312323134  lorem ipsum
5         11        67890   325565454  dolor
6         11        34355   333544664  samet

Each tweet should only appear once in the database. As you can see, the exact same tweet (same call_id, id_str, timestamp and text – on other words everything is the same except for the tweet_id (which is an autonumbering field)) has been stored 4 times (!)

Is there a way to exact matches (so: same everything except tweet_id) and then delete the last x – 1 (here: 4 -1 = 3) of them? In other words, the cleaned-up table would look like

tweet_id  call_id   id_str  timestamp  text
--------------------------------------------------
1         11        12345   312323134  lorem ipsum
5         11        67890   325565454  dolor
6         11        34355   333544664  samet

I hope there’s an easy way to do this, because otherwise I have a huge problem (shows you what putting in an extra hour of thinking before you actually build your database can do!)

Answer 1

have you searched for a solution online before asking this question ???? if not here is an online tutorial on how to do this.

http://www.sqlteam.com/article/deleting-duplicate-records