相同列的条件更新

Question

Pl找到下面的代码

SQL> desc aaa
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 ENAME                                              VARCHAR2(1)

SQL> select * from aaa;

E
-
2
2
2
5
5
5
5

7 rows selected.  

我需要使用单个sql以5和5更新2和2.

Answer 1

update
  aaa
set
  ENAME = case when ENAME = '2' then '5' else '2' end
where
  ENAME in ('2', '5')