MySQL 지정 연산자

Assignment Operators 

지정 연산자쯤 되겠지?

 

Name	Description
:=	Assign a value
=	Assign a value(as part of a SET statement, or as part of the SET clause in an UPDATE statement)

 

1) :=

Assignment operator

 

흠.. 거의 사용을 안해봐서... 그냥 예제만

 

mysql> SELECT @var1 :=1 , @var2 ;
+-----------+-------+
| @var1 :=1 | @var2 |
+-----------+-------+
|         1 | NULL  |
+-----------+-------+
1 row in set, 1 warning (0.01 sec)

mysql> SELECT @var1, @var2 ;
+-------+-------+
| @var1 | @var2 |
+-------+-------+
|     1 | NULL  |
+-------+-------+
1 row in set (0.00 sec)

mysql> SELECT @var1, @var2 := @var1 ;
+-------+----------------+
| @var1 | @var2 := @var1 |
+-------+----------------+
|     1 |              1 |
+-------+----------------+
1 row in set, 1 warning (0.00 sec)

mysql> SELECT @var1, @var2 ;
+-------+-------+
| @var1 | @var2 |
+-------+-------+
|     1 |     1 |
+-------+-------+
1 row in set (0.01 sec)

 

 

2) =

생략.