mysql join remove duplicate columns code example
Example 1: mysql remove duplicates
DELETE FROM table_name WHERE id
NOT IN ( SELECT id FROM table_name
GROUP BY field_1, field_2)
Example 2: mysql remove duplicates
DELETE t1 FROM contacts t1
INNER JOIN contacts t2
WHERE
t1.id < t2.id AND
t1.email = t2.email;Code language: SQL (Structured Query Language) (sql)