mysql> create table users(num int not null, id varchar(30) not null, password varchar(30) not null, primary key(num));

Query OK, 0 rows affected (0.00 sec)

mysql> insert into users values(1, ‘admin’, ‘ad1234’);

Query OK, 1 row affected (0.00 sec)

mysql> insert into users values(2, ‘wh1ant’, ‘wh1234’);

Query OK, 1 row affected (0.00 sec)

mysql> insert into users values(3, ‘secuholic’, ‘se1234’);

Query OK, 1 row affected (0.00 sec)

mysql> select * from users where id=0;

+—–+———–+———-+

| num | id        | password |

+—–+———–+———-+

|   1 | admin     | ad1234   |

|   2 | wh1ant    | wh1234   |

|   3 | secuholic | se1234   |

+—–+———–+———-+

3 rows in set, 3 warnings (0.00 sec)

mysql> show warnings

-> ;

+———+——+———————————————–+

| Level   | Code | Message                                       |

+———+——+———————————————–+

| Warning | 1292 | Truncated incorrect DOUBLE value: ‘admin’     |

| Warning | 1292 | Truncated incorrect DOUBLE value: ‘wh1ant’    |

| Warning | 1292 | Truncated incorrect DOUBLE value: ‘secuholic’ |

+———+——+———————————————–+

3 rows in set (0.00 sec)

mysql> select * from users where id=’0′;

Empty set (0.00 sec)

mysql> select * from users where 0=id;

+—–+———–+———-+

| num | id        | password |

+—–+———–+———-+

|   1 | admin     | ad1234   |

|   2 | wh1ant    | wh1234   |

|   3 | secuholic | se1234   |

+—–+———–+———-+

3 rows in set, 3 warnings (0.00 sec)

mysql> insert into users values(‘ucjmh’,’ucjmh’,’ucjmh’);

Query OK, 1 row affected, 1 warning (0.00 sec)

mysql> show warnings;

+———+——+————————————————————+

| Level   | Code | Message                                                    |

+———+——+————————————————————+

| Warning | 1366 | Incorrect integer value: ‘ucjmh’ for column ‘num’ at row 1 |

+———+——+————————————————————+

1 row in set (0.00 sec)

mysql> select * from users;

+—–+———–+———-+

| num | id        | password |

+—–+———–+———-+

|   0 | ucjmh     | ucjmh    |

|   1 | admin     | ad1234   |

|   2 | wh1ant    | wh1234   |

|   3 | secuholic | se1234   |

+—–+———–+———-+

4 rows in set (0.00 sec)