Oct 19 2012

Remove duplicate entries from mysql table

By • Mysql • 0 • Tags: ,

This specific content was written 13 years ago. Please keep this in mind as it may be outdated and not adhering to best-practices.

Was writing some code, and dealt with this problem…so posting about solving this problem with 1 command (or more) depending on your decision.If you want to remove all duplicate rows with the same combination of N number of columns.

I’ll talk about two options in this post:

Add a unique key constraint that drops all duplicates

This one will remove all duplicates (based on the combination of columns you give) with one line.
The approach works by altering the table, and adding a unique key. Applying this unique key, causes all duplicate rows to be dropped leaving only one.

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