Schema of logininfo table

+----------+-------------+------+-----+---------+-------+
| Field    | Type        | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+-------+
| login    | varchar(10) |      | PRI |         |       |
| password | varchar(10) | YES  |     | NULL    |       |
| name     | varchar(20) | YES  |     | NULL    |       |
+----------+-------------+------+-----+---------+-------+


Schema of subjectinfo table

+-------------+-------------+------+-----+---------+-------+
| Field       | Type        | Null | Key | Default | Extra |
+-------------+-------------+------+-----+---------+-------+
| subjectid   | int(2)      |      | PRI | 0       |       |
| subjectname | varchar(20) | YES  |     | NULL    |       |
+-------------+-------------+------+-----+---------+-------+

Schema of marks table

+-----------+-------------+------+-----+---------+-------+
| Field     | Type        | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------+-------+
| loginid   | varchar(10) |      | PRI |         |       |
| subjectid | int(2)      |      | PRI | 0       |       |
| marks     | int(2)      | YES  |     | NULL    |       |
+-----------+-------------+------+-----+---------+-------+

