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Databases

How to remove duplicate rows in SQL (works with Postgres)

Note to self more than anything, this snippet was handy for to remove duplicate rows in SQL, that crept into a Postgres database as a result of a dodgy join. There are probably more than a couple of ways of doing this but the best example I came up with after reading around is: DELETE FROM table_nameWHERE ctid NOT IN ( SELECT min(ctid) FROM table_name GROUP BY field1, field2); The reason this works revolves around the ctid field. This is a default field you don't have to specify Read more [...]