Question

我有一张表格如图所示

 CREATE TABLE `document` (
  `T1` varchar(50) DEFAULT NULL,
  `T2` varchar(50) DEFAULT NULL,
  `T3` varchar(50) DEFAULT NULL,
  `T4` varchar(50) DEFAULT NULL,
  `T5` varchar(50) DEFAULT NULL,
   status int default 0 
);

Insert into document (T1 , status ) values ('Pocorn',0);
Insert into document (T1 , T2  , status ) values ('Pocorn', 'Bucket' , 1);
Insert into document (T1 , T2 , T3 , status) values ('Pocorn', 'Chocka' , 'Small' , 2);

这是我的sqlfiddle http://sqlfiddle.com/#!2/d816e/2

我的问题是我有3个身份

0表示待定

1表示已批准

2表示拒绝

是否可以在提取时将值替换为待处理，已批准和已拒绝

Answer 1

select t1, t2, t3, t4, 
case 
  when status=0 then 'Pendig'
  when status=1 then 'Approved'
  when status=2 then 'Declined'
  end
  from document

Answer 2

select case when status = 0
            then 'pending'
            when status = 1
            then 'approved'
            when status = 2
            then 'declined'
       end as status
from document

如何在获取自身时替换值

2 个答案:

SQLFiddle