数据库去重

查询
SELECT
*
FROM
table A
WHERE
( A.the_date, A.exponent_code, A.exponent_value ) IN ( SELECT the_date, exponent_code, exponent_value FROM table GROUP BY the_date, exponent_code, exponent_value HAVING COUNT ( * ) > 1 )
AND A.ID NOT IN ( SELECT MIN ( ID ) FROM table GROUP BY the_date, exponent_code, exponent_value HAVING COUNT ( * ) > 1 )
LIMIT 10000 OFFSET 1

删除相同指标()
DELETE
FROM
table A
WHERE
( A.the_date, A.exponent_code, A.exponent_value ) IN ( SELECT the_date, exponent_code, exponent_value FROM table GROUP BY the_date, exponent_code, exponent_value HAVING COUNT ( * ) > 1 )
AND A.ID NOT IN ( SELECT MIN ( ID ) FROM table GROUP BY the_date, exponent_code, exponent_value HAVING COUNT ( * ) > 1 )

注:

A为数据表代替名,可忽略不改

the_date, exponent_code, exponent_value为表字段名,多或单个字段联合唯一

table为数据库表名

原文地址:https://www.cnblogs.com/xiaowangba9494/p/13299658.html