Posted on May 20, 2017 at 10:23 am
Fastest ways to find duplicate records in MySQL.
If name is the column you want to find duplicates in:
SELECT col1 FROM table GROUP BY col1 HAVING count(*) > 1; |
Is also possible to support multiple columns, like this:
SELECT col1, col2, COUNT(*) c FROM table GROUP BY col1, col2 HAVING c > 1; |
Get the IDs of the duplicate rows with GROUP_CONCAT:
SELECT GROUP_CONCAT(id), name, COUNT(*) c FROM table GROUP BY name HAVING c > 1; |
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