Mysql数据重复问题处理
发布时间：2022-09-30 12:52:47 所属栏目：MySql教程 来源：
导读： 当一某个字段重复判断重复时 ：查询重复数据 重复取id最小值
select table,min(id)
from table
where “字段” = 'xx'
group by “重复字段” hav
select table,min(id)
from table
where “字段” = 'xx'
group by “重复字段” hav
|
当一某个字段重复判断重复时 ：查询重复数据 重复取id最小值 select table,min(id) from table where “字段” = 'xx' group by “重复字段” having count(1) > 1 ; 查询影响条数 select * from table where " 字段"= 'xx' and id not in (select min(id) from table where "字段" = 'xx' MySQL 处理重复数据_处理数据库中重复数据_mysql 取出重复数据 group by "重复字段" having count(1) > 1 ) and "重复字段" in (select "重复字段" from table where "字段" = 'xx' group by "重复字段"having count(1) > 1 ); 删除 delete from table where "字段" = 'xx' and id not in (select a.* from (select min(id) mysql 取出重复数据_MySQL 处理重复数据_处理数据库中重复数据 from table where "字段" = 'xx' group by 重复字段 having count(1) > 1 ) a ) and "重复字段" in (select b.* from (select "重复字段" from table where "字段" = 'xx' group by "重复字段"having count(1) > 1 ) b); 所有字段重复时：使用 distinct insert into table1 select distinct * from table ; ALTER TABLE table RENAME TO table_20220908; ALTER TABLE table1RENAME TO table . （编辑：百客网 - 域百科网） 【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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