TableName : yourtablename

Existed Fields: yourfield1,yourfield2, handle.......

删除指定字段yourfield1为MatchedString所所有重复项

delete * from yourtablename where yourfield1='MatchedString' and handle not in (select distinct min(Handle) from chnl where yourfield1='MatchedString')

删除数据库中所有存在重复项的字段

delete * from yourtablename where handle not in (select distinct min(handle) from yourtablename group by  yourfield1)

Sql操作 - 删除数据库重复项