select count(*),oId from afl_taobao_rate group by oId order by count(*) desc
afl_taobao_rate 裏面的oid重複,要求重複只留一條
1.建立臨時表
create table tmp as select * from afl_taobao_rate group by oId
2.給臨時表加uniqu限制
ALTER TABLE tmp ADD unique(`oId`);
3.備份原始表
alter table afl_taobao_rate rename afl_taobao_rate2
4.將臨時表 改爲目標表
alter table tmp rename afl_taobao_rate