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sqlserver删除数据冗余，高手请解释下！thank you
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- 2016-06-07 15:34:061150browse
思路？大哥你几年级的 看条件 where ConID = t.ConID and len (GeoNo) len (t.GeoNo) 把 Insert into tb_Table (GeoNo,Title,ConID) values ('01','北京','1000') Insert into tb_Table (GeoNo,Title,ConID) values ('0101','海淀区','1000') Insert into tb
思路？大哥你几年级的
看条件where ConID=t.ConID andlen(GeoNo)>len(t.GeoNo)
把
Insert into tb_Table (GeoNo,Title,ConID) values ('01','北京','1000')
Insert into tb_Table (GeoNo,Title,ConID) values ('0101','海淀区','1000')
Insert into tb_Table (GeoNo,Title,ConID) values ('010101','上地','1000')
弄成
Insert into tb_Table (GeoNo,Title,ConID) values ('010101','上地','1000')
这3条的ConID相同，留下GeoNo长度最大的
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