Can we compare numbers in a MySQL varchar field?
Yes, we can do this by first using CAST(). Let us first create a table −
mysql> create table DemoTable
-> (
-> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> StudentScore varchar(100)
-> );
Query OK, 0 rows affected (0.66 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable(StudentScore) values('90');
Query OK, 1 row affected (0.21 sec)
mysql> insert into DemoTable(StudentScore) values('100');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable(StudentScore) values('56');
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable(StudentScore) values('98');
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 −
+-----------+--------------+
| StudentId | StudentScore |
+-----------+--------------+
| 1 | 90 |
| 2 | 100 |
| 3 | 56 |
| 4 | 98 |
+-----------+--------------+
4 rows in set (0.00 sec)
Here is the query to compare in varchar fields −
mysql> select *from DemoTable where CAST(StudentScore AS SIGNED) > 91;
This will produce the following output −
+-----------+--------------+
| StudentId | StudentScore |
+-----------+--------------+
| 2 | 100 |
| 4 | 98 |
+-----------+--------------+
2 rows in set (0.00 sec)
Published on 11-Jul-2019 15:11:07
