MySQL中删除重复数据只保留一条

一.删除数据库中的重复数据, 只留一条

-- 删除数据库中的重复数据只留一条
DELETE 
FROM
    crm_member 
WHERE
    id IN (
    SELECT
        a.id 
    FROM
        (
        SELECT
            id 
        FROM
            crm_member 
        WHERE
            phone IN ( SELECT phone FROM crm_member GROUP BY phone HAVING count( phone ) > 1 ) 
            AND id NOT IN ( SELECT min( id ) FROM crm_member GROUP BY phone HAVING count( phone ) > 1 ) 
        ) a 
    )