Assign value to a variable with := : Variable « Select Clause « SQL / MySQL






Assign value to a variable with :=

       
mysql>
mysql>
mysql> CREATE   TABLE PENALTIES
    ->         (PAYMENTNO      INTEGER      NOT NULL,
    ->          EmployeeNO       INTEGER      NOT NULL,
    ->          PAYMENT_DATE   DATE         NOT NULL,
    ->          AMOUNT         DECIMAL(7,2) NOT NULL,
    ->          PRIMARY KEY    (PAYMENTNO)          );
mysql>
mysql> INSERT INTO PENALTIES VALUES (1,  6, '1980-12-08',100);
mysql> INSERT INTO PENALTIES VALUES (2, 44, '1981-05-05', 75);
mysql> INSERT INTO PENALTIES VALUES (3, 27, '1983-09-10',100);
mysql> INSERT INTO PENALTIES VALUES (4,104, '1984-12-08', 50);
mysql> INSERT INTO PENALTIES VALUES (5, 44, '1980-12-08', 25);
mysql> INSERT INTO PENALTIES VALUES (6,  8, '1980-12-08', 25);
mysql> INSERT INTO PENALTIES VALUES (7, 44, '1982-12-30', 30);
mysql> INSERT INTO PENALTIES VALUES (8, 27, '1984-11-12', 75);
mysql>
mysql> SELECT   @VAR := SUM(AMOUNT)
    -> FROM     PENALTIES;
+---------------------+
| @VAR := SUM(AMOUNT) |
+---------------------+
|              480.00 |
+---------------------+
1 row in set (0.00 sec)

mysql>
mysql> drop table penalties;
Query OK, 0 rows affected (0.00 sec)

mysql>

   
    
    
    
    
    
    
  








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