SQLSERVER 表数据大量重复

前几天查看数据库,发现有表有大量重复数据。

下面是去除重复数据的方法,不知道有没有更好的办法:

1、去除重复的最大ID

--t_CAR 表去重
delete t_car where car_id in(
select max(car_id)  from t_car where 1=1
 group by car_num having count(1)>1 
)

2、部分数据重复出现多次,执行1000次循环

declare @num int 
declare @end int 
set @num=0 
set @end=1000
while @num<@end
begin
delete t_car where car_id in(
select max(car_id)  from t_car where 1=1
 group by car_num having count(1)>1 
)
set @num = @num+1
end 

总结:方法比较笨,也实现了功能;不知道有没有更好的办法

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转载自koyomagic.iteye.com/blog/1985614