1、查詢表中重復數據。select * from people where peopleId in (select peopleId from people group ...
查詢表中重復數據 select from employee where employeeId in select employeeId from employee group by employeeId having count employeeId gt 刪除表中多余的重復記錄,重復記錄是根據單個字段 employeeId 來判斷,只留有rowid最小的記錄 delete from employ ...
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1、查詢表中重復數據。select * from people where peopleId in (select peopleId from people group ...
來自 王濤 同志的指導 DELETE FROM product WHERE searchdate IN (SELECT sd FROM (SELECT a.searchdate sd FROM pr ...
刪除數據庫中重復的記錄,只保留一條 DELETE FROM tb_gps_records WHERE id NOT IN (SELECT bid FROM (SELECT min(id) as bid FROM tb_gps_records GROUP BY busNo,longitude ...
表名:hztj 字段名:edxzqhdm ,sdxzqhdm 1.查出某一列數據中重復的,以sdxzqhdm為例 select * from hztj a where (a.sdxzqhdm) in (select sdxzqhdm from hztj group by sdxzqhdm ...
create table Student( ID varchar(10) not null, Name varchar(10) not null, ); insert ...
在執行語句時難免會輸入相同的數據,這些重復記錄不但沒有用,還可能導致數據庫占用大量資料或導致數據庫查詢索引無效。 如果在建表的時候沒有設置主鍵或unique索引,那么插入完全重復的數據是不會報錯的,結果就是無法修改記錄行或者刪除記錄行。通過SQL語句可以實現刪除表中重復數據。 所有字段均重復 ...
在幾千條記錄里,存在着些相同的記錄,如何能用SQL語句,刪除掉重復的呢1、查找表中多余的重復記錄,重復記錄是根據單個字段(peopleId)來判斷 select * from people where peopleId in (select peopleId from people ...
查詢及刪除重復記錄的SQL語句 1、查找表中多余的重復記錄,重復記錄是根據單個字段(Id)來判斷 2、刪除表中多余的重復記錄,重復記錄是根據單個字段(Id)來判斷,只留有rowid最小的記錄 3、查找表中多余的重復記錄(多個字段) 4、刪除表中多余的重復記錄(多個字段),只留有 ...