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mysql怎么取重复记录 mysql 重复

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mysql的sql语句如何去掉重复的数据难倒只能分步操作，蛋疼
以下是网友写的，同样是坑爹的代码，我机器上运行不了 。
【mysql怎么取重复记录 mysql 重复】1. 查询需要删除的记录 ， 会保留一条记录 。
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select a.id,a.subject,a.RECEIVER from test1 a left join (select c.subject,c.RECEIVER ,max(c.id) as bid from test1 c where status=0 GROUP BY RECEIVER,SUBJECT having count(1) 1) b on a.id b.bid where a.subject=b.subject and a.RECEIVER = b.RECEIVER and a.idb.bid
2. 删除重复记录，只保留一条记录 。注意，subject,RECEIVER 要索引，否则会很慢的 。
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delete a from test1 a, (select c.subject,c.RECEIVER ,max(c.id) as bid from test1 c where status=0 GROUP BY RECEIVER,SUBJECT having count(1) 1) b where a.subject=b.subject and a.RECEIVER = b.RECEIVER and a.idb.bid;
3. 查找表中多余的重复记录，重复记录是根据单个字段（peopleId）来判断
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select * from people where peopleId in (select peopleId from people group by peopleId having count(peopleId)1)
4. 删除表中多余的重复记录 ， 重复记录是根据单个字段（peopleId）来判断，只留有rowid最小的记录
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mysql如何查询重复记录select * from tableName where (bookname,borrowtime) in (select bookname,borrowtime from tableName group by bookname,borrowtime having count(*)1);
如何使用 sql (mysql)查询任意两条重复的记录?select * from 用户表 where 用户名 in (select 用户名 from 用户表 group by 用户名 having count(1)1)
mysql去重复 保留一条mysql去重复 保留一条怎么操作呢？一起来看下吧mysql怎么取重复记录：
1、查找表中多余mysql怎么取重复记录的重复记录mysql怎么取重复记录，重复记录是根据单个字段（peopleId）来判断
SELECT*FROMpeopleWHEREpeopleId IN (SELECTpeopleIdFROMpeopleGROUP BYpeopleIdHAVINGcount(peopleId)1)
2、删除表中多余的重复记录mysql怎么取重复记录，重复记录是根据单个字段（peopleId）来判断mysql怎么取重复记录，只留有rowid最小的记录
DELETEFROMpeopleWHEREpeopleName IN (SELECTpeopleNameFROMpeopleGROUP BYpeopleNameHAVINGcount(peopleName)1)AND peopleId NOT IN (SELECTmin(peopleId)FROMpeopleGROUP BYpeopleNameHAVINGcount(peopleName)1)
3、查找表中多余的重复记录（多个字段）
SELECT*FROMvitae aWHERE(a.peopleId, a.seq) IN (SELECTpeopleId,seqFROMvitaeGROUP BYpeopleId,seqHAVINGcount(*)1)
4、删除表中多余的重复记录（多个字段），只留有rowid最小的记录
DELETEFROMvitae aWHERE(a.peopleId, a.seq) IN (SELECTpeopleId,seqFROMvitaeGROUP BYpeopleId,seqHAVINGcount(*)1)AND rowid NOT IN (SELECTmin(rowid)FROMvitaeGROUP BYpeopleId,seqHAVINGcount(*)1)
5、查找表中多余的重复记录（多个字段），不包含rowid最小的记录
SELECT*FROMvitae aWHERE(a.peopleId, a.seq) IN (SELECTpeopleId,seqFROMvitaeGROUP BYpeopleId,seqHAVINGcount(*)1)AND rowid NOT IN (SELECTmin(rowid)FROMvitaeGROUP BYpeopleId,seqHAVINGcount(*)1)
6、消除一个字段的左边的第一位：
UPDATE tableNameSET [ Title ]= RIGHT ([ Title ],(len([ Title ]) - 1))WHERETitle LIKE '村%'
7、消除一个字段的右边的第一位：
UPDATE tableNameSET [ Title ]= LEFT ([ Title ],(len([ Title ]) - 1))WHERETitle LIKE '%村'
8、假删除表中多余的重复记录（多个字段），不包含rowid最小的记录
UPDATE vitaeSET ispass =- 1WHEREpeopleId IN (SELECTpeopleIdFROMvitaeGROUP BYpeopleId
MySql怎么查询重复的数据select name,sum(num) from table group by name
--group by 分组查询可以实现mysql怎么取重复记录 ， 根据名称分组查询累加数量
mysql 怎样找出重复的记录SQL语句：SELECT `lcontent` FROM `caiji_ym_liuyan`这样查询的时候就会有很多重复的记录
例子：
就会出现这样的重复
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修改后的SQL语句：
SELECT distinct(`lcontent`) FROM `caiji_ym_liuyan`
查询结果：
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