mysql ignore duplicate values in column code example
Example 1: mysql delete duplicate rows but keep one
DELETE c1 FROM contacts c1
INNER JOIN contacts c2
WHERE
c1.id > c2.id AND
c1.email = c2.email;
Example 2: mysql delete duplicate rows except one
DELETE FROM NAMES
WHERE id NOT IN (SELECT *
FROM (SELECT MIN(n.id)
FROM NAMES n
GROUP BY n.name) x)