oracle中刪除重復(fù)記錄-預(yù)覽頁
【正文】 2 dsf 1 2 dsf 1 2 dsf 2 3 che 1 2 dsf 1 2 dsf 1 2 dsf 1 2 dsf 2 3 che 2 3 che 2 3 che 2 3 che 3 4 dff 3 4 dff 3 4 dff 4 5 err 5 3 dar 6 1 wee 7 2 zxc20 rows selected.：(1).sqlselect * from cz group by c1,c10,c20 having count(*) 1。sqldelete cz where rowid not in(select min(rowid) from cz group by c1,c10,c20)。(3).適用于有少量重復(fù)記錄的情況(臨時表法)：sqlcreate table test as select distinct * from cz。這種方法稍微麻煩一些，為了使用“excepeion into ”子句，必須首先創(chuàng)建 exceptions 表。 *error at line 1:ora02299: cannot validate () duplicate keys foundsqlcreate table dups as select * from cz where rowid in (select row_id from exceptions)。16 rows deleted.sqlinsert into cz select distinct * from dups
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