mysql C 使用GROUP BY删除重复项的查询
发布时间:2023-12-20 04:26:59 所属栏目:MySql 来源:DaWei
导读: id_specific_price id_product
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id_specific_price id_product ------------------------------- 1 2 2 2 3 2 4 3 5 3 6 3 7 3 需要删除重复项,预期结果: id_specific_price id_product ------------------------------- 3 2 7 3 SELECT * FROM ps_specific_price WHERE id_specific_price NOT IN (SELECT MAX(id_specific_price) FROM ps_specific_price GROUP BY id_product)工作,但 DELETE FROM ps_specific_price WHERE id_specific_price NOT IN (SELECT MAX(id_specific_price) FROM ps_specific_price GROUP BY id_product)才不是.有很多例子可以解决这个问题,但由于某种原因,我无法适应它.我相信它是GROUP BY.例如: DELETE FROM ps_specific_price WHERE id_specific_price NOT IN (SELECT MAX(p.id_specific_price) FROM (SELECT * FROM ps_specific_price ) as p) GROUP BY id_product我在哪里错了? 最佳答案 如果您正在寻找MySQL的解决方案,那么您可以使用正确的multi table DELETE语法以及这样的JOIN DELETE p FROM ps_specific_price p JOIN ( SELECT id_product,MAX(id_specific_price) id_specific_price FROM ps_specific_price GROUP BY id_product ) d ON p.id_product = d.id_product AND p.id_specific_price(编辑:4S站长网) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |
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