MYSQL如何修改查询出来的结果集

  update expresspackage  set IsUploadSto=-200  where BillCode in
   (
       SELECT BillCode from expresspackage where RealLatticeNo not in (224,448) and 
       `Status` = 0 and DownTime < '2022/1/26 15:29:03' and 
       createTime < '2022/1/26 15:29:03' and IsUploadSto > -20 and IsUploadSto < 1
   )
执行上诉语句出现You can't specify target table for update in FROM clause 不能在同一表中查询的数据作为同一表的更新数据。

改成下述语句就行

  update expresspackage  set IsUploadSto=-200  where BillCode in
   (
   SELECT a.BillCode from 
   (
   SELECT BillCode from expresspackage where RealLatticeNo not in (224,448) and 
   `Status` = 0 and DownTime < '2022/1/26 15:29:03' and 
   createTime < '2022/1/26 15:29:03' and IsUploadSto > -20 and IsUploadSto < 1
   ) a
   )
也就是说将select出的结果再通过中间表select一遍,这样就规避了错误。注意,这个问题只出现于mysql,mssql和Oracle不会出现此问题。

 

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