在以下查询中使用'case'语句的位置？

Question

这是问题陈述给我：

create or replace function disp_player_name (play_id in number) 
return varchar is status_name varchar(100); 
begin 
select country into status_name from player where id=play_id; 
return status_name; exception 
when no_data_found then status_name := 'No such country' 
return status_name; 
end;/ 

我应该在哪里使用“案例”作为问题陈述给打印状态？

Answer 1

这绝对看起来像功课，但正好在你的SELECT INTO之后。

create or replace function disp_player_name (play_id in number) 
return varchar is status_name varchar(100); 
begin 

select country into status_name from player where id=play_id; 

CASE 
      WHEN status_name = 'India' THEN 
       status_name := 'Player belongs to India'; 

END CASE; 

return status_name; 

exception 
when CASE_NOT_FOUND then status_name := 'No such country' 

return status_name; 
end;/