SQL - 在列中选择相同的值，然后重命名它们

Question

SQL中是否可以选择列中的值然后重命名重复的值？ （假设最大的一个可能重复的只）

比方说，我有一个表..

| id | name | 0or1_id | 
| 0 | Eddy | 0  | 
| 1 | Allan | 0  | 
| 2 | Eddy | 1  | 
| 3 | Allan | 1  | 

我能做些什么，查询，使它象这样？

| id | name  | 0or1_id | 
| 0 | Eddy  | 0  | 
| 1 | Allan  | 0  | 
| 2 | Eddy-copy | 1  | 
| 3 | Allan-copy | 1  | 

Answer 1

假设你想真正改变数据，使用update：

update t join 
     (select name, count(*) as cnt, min(id) as minid 
     from t 
     group by name 
     having cnt > 1 
     ) tt 
     on t.name = tt.name and t.id <> tt.minid 
    set name = concat(name, '-copy'); 

如果你只想要一个select，那么逻辑非常相似。

Answer 2

这将在SQL Server的工作..

select id , name ,0or1_id from (
select id , name ,0or1_id ,row_number() over (partition by name order by id) as rnm 
from table)z1 
where rnm =1 
union 
select id , name || '- Copy' as new_name ,0or1_id from (
select id , name ,0or1_id ,row_number() over (partition by name order by id) as rnm 
from table)z2 
where rnm > 2 

Answer 3

http://sqlfiddle.com/#!9/3ebaf/1

UPDATE mytable t 
INNER JOIN mytable t1 
ON t.name = t1.name 
    AND t.id>t1.id 
SET t.name = CONCAT(t.name,'-copy');