MYSQL if statement question

Question

 
Is there any way to get the if statement to evaluate a query? 

SELECT if(5>0,'EQ_Type','*') FROM EQUIPMENT; 

Resulting in: 
+-----------------------+ 
| IF(5>0,'EQ_Type','*') | 
+-----------------------+ 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
| EQ_Type    | 
+-----------------------+ 
9 rows in set (0.00 sec) 




I would like the above statement to be equivalent to the following: 

SELECT 'EQ_Type' FROM EQUIPMENT; 

And produce: 
+--------------+ 
| EQ_Type  | 
+--------------+ 
| ENGINE  | 
| ENGINE  | 
| ENGINE  | 
| TRAILER  | 
| TRAILER  | 
| TRAILER  | 
| WATER TENDER | 
| WATER TENDER | 
| WATER TENDER | 
+--------------+ 


Thanks for any help 

Answer 1

只删除单引号。在这种情况下CASE statements - -

SELECT if(5>0,EQ_Type,'*') FROM EQUIPMENT; 

Answer 2

我建议使用ANSI符号，而不是MySQL的特定语法：

SELECT CASE WHEN 5 > 0 THEN t.eq_type ELSE '*' END 
    FROM EQUIPMENT t 

原因是，如果你改变了数据库 - 这种说法不会需要改变工作在Oracle，Postgres，SQL Server等上。