SQL variables may be used to store the results of intermediate calculations. : Variable « Select Clause « SQL / MySQL






  1. SQL / MySQL
  2. Select Clause
  3. Variable

SQL variables may be used to store the results of intermediate calculations.

       
mysql>
mysql> SET @daily_room_charge = 100.00;
Query OK, 0 rows affected (0.00 sec)

mysql> SET @num_of_nights = 3;
Query OK, 0 rows affected (0.00 sec)

mysql> SET @tax_percent = 8;
Query OK, 0 rows affected (0.00 sec)

mysql> SET @total_room_charge = @daily_room_charge * @num_of_nights;
Query OK, 0 rows affected (0.00 sec)

mysql> SET @tax = (@total_room_charge * @tax_percent) / 100;
Query OK, 0 rows affected (0.00 sec)

mysql> SET @total = @total_room_charge + @tax;
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT @total;
+---------------+
| @total        |
+---------------+
| 324.000000000 |
+---------------+
1 row in set (0.00 sec)

mysql>








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