mysql數(shù)據(jù)庫(kù) 查詢，mysql數(shù)據(jù)庫(kù)中怎么刪除重復(fù)的數(shù)據(jù)？
1. 查詢需要?jiǎng)h除的記錄，會(huì)保留一條記錄。 select a.id,a.subject,a.RECEIVER from test1 a left join (select c.subject,c.RECEIVER ,max(c.id) as bid from test1 c where status=0 GROUP BY RECEIVER,SUBJECT having count(1) >1) b on a.id1) b where a.subject=b.subject and a.RECEIVER = b.RECEIVER and a.id
