Question

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Remove duplicate rows from table with join

My table looks like this:
a,b,c,d,date
How to remove all rows with same a,b,c and d except row with latest date?
There is some rows, that has a and b same and c and d NOT same.

Answer 1

Try this:

DELETE FROM tableName 
WHERE (a, b, c, d, dte) NOT IN (SELECT a, b, c, d, dte 
                                FROM (SELECT a, b, c, d, MAX(dte) dte 
                                     FROM tableName GROUP BY a, b, c, d
                                ) AS A );

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