Mysql如何去掉數(shù)據(jù)庫(kù)中的重復(fù)記錄？很簡(jiǎn)單 通過id刪除DELETE FROMtable_name AS ta WHEREta.唯一鍵 <> (SELECTt.maxid FROM( SEL

Mysql如何去掉數(shù)據(jù)庫(kù)中的重復(fù)記錄？

很簡(jiǎn)單 通過id刪除

DELETE

FROM

table_name AS ta

WHERE

ta.唯一鍵 <> (

SELECT

t.maxid

FROM

( SELECT max( tb.唯一鍵 ) AS maxid FROM table_name AS tb WHERE ta.判斷重復(fù)的列 = tb.判斷重復(fù)的列 ) t

)

Mysql數(shù)據(jù)庫(kù)中多條重復(fù)數(shù)據(jù)，如何只刪除一條？

列出要保留的記錄ID，可以把這個(gè)結(jié)果寫到一個(gè)臨時(shí)表t1中： SELECT MAX(id) AS max_id FROM pedigree GROUP BY number然后：DELETE FROM pedigree WHERE id NOT IN (SELECT id FROM t1)也就是：delete from pedigree where id not in(select * from pedigree where group by number)。pedigree where id not in(select max(id) from pedigree where group by number having count(id) > 0) 查詢結(jié)果是否符合刪除要求！