Increase database field value by specified percentage using user-defined variables in MySQL
Let us first create a table −
mysql> create table DemoTable
-> (
-> Amount int
-> );
Query OK, 0 rows affected (0.99 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable values(100);
Query OK, 1 row affected (0.23 sec)
mysql> insert into DemoTable values(200);
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable values(500);
Query OK, 1 row affected (0.13 sec)
Display all records from the table using select statement −
mysql> select *from DemoTable;
This will produce the following output −
+--------+
| Amount |
+--------+
| 100 |
| 200 |
| 500 |
+--------+
3 rows in set (0.00 sec)
Following is the query to increase database field value by specified percentage −
mysql> set @rate=10;
Query OK, 0 rows affected (0.00 sec)
mysql> update DemoTable
-> set Amount=Amount*(1+@rate/100);
Query OK, 3 rows affected (0.18 sec)
Rows matched: 3 Changed: 3 Warnings: 0
Let us check table records once again −
mysql> select *from DemoTable;
This will produce the following output −
+--------+
| Amount |
+--------+
| 110 |
| 220 |
| 550 |
+--------+
3 rows in set (0.00 sec)
Published on 12-Jul-2019 16:27:05
