szhswl
          宋針還的個人空間

          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 group by peopleId having count(peopleId) > 1)

          2、刪除表中多余的重復記錄,重復記錄是根據單個字段(peopleId)來判斷,只留有rowid最小的記錄
          delete from people
          where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
          and rowid not in (select min(rowid) from people group by peopleId having count(peopleId )>1)

          3、查找表中多余的重復記錄(多個字段)
          select * from vitae a
          where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)

          4、刪除表中多余的重復記錄(多個字段),只留有rowid最小的記錄
          delete from vitae a
          where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
          and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)

          5、查找表中多余的重復記錄(多個字段),不包含rowid最小的記錄
          select * from vitae a
          where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
          and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)


          利用rowid重復記錄的查詢還可以用下面SQL:
          select * from people p1
          where p1.rowid not in (select max(rowid) from people p2 where p2.peopleId = p1.peopleId)

          ---------------------------------------------------------------------------------------------------------------------------------
          說人之短,乃護己之短。夸己之長,乃忌人之長。皆由存心不厚,識量太狹耳。能去此弊,可以進德,可以遠怨。
          http://www.aygfsteel.com/szhswl
          ------------------------------------------------------------------------------------------------------ ----------------- ---------
          posted on 2007-12-03 15:48 宋針還 閱讀(724) 評論(0)  編輯  收藏 所屬分類: SQL
          主站蜘蛛池模板: 南雄市| 泸溪县| 紫阳县| 当阳市| 遂平县| 滦平县| 枣阳市| 格尔木市| 遂溪县| 竹山县| 绿春县| 西城区| 繁峙县| 文安县| 商丘市| 罗江县| 青川县| 梅州市| 祁阳县| 全州县| 启东市| 瓦房店市| 海原县| 淮阳县| 临江市| 丹凤县| 龙江县| 金昌市| 丽水市| 克拉玛依市| 曲周县| 凤凰县| 康乐县| 齐齐哈尔市| 江华| 怀安县| 上杭县| 全南县| 屯昌县| 玉林市| 岳阳县|