Hi,

I have a little MySQL database - actually it's not that little, it has about 252,000 records in it. The trouble is many of these records contain duplicate information. I need to analyse each record and remove this duplicate information.

Obviously each record has it's own unique primary key, but I need to compare say 5 out of the total of 9 fields in each record and if they contain duplicate information, just drop the one.

Now I could do this by taking record 1, looping in perl and comparing it to every other record, then when I find one that matches, drop that record. But that would take ages!!!

I was just wondering if anyone knew a cool, quick and easy MySQL command that would do it for me...?<?p>

MySQL seems to be good at stuff like that.

Your hopefully,
Tom

In reply to Removing duplicates in MySQL by shaolin_gungfu

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