mySQL adding column breaks data - mysql

Question

I have succesfully created a database in mySQL using the commandline and imported some data. It currently looks like this..
desc data;
+----------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| code | varchar(10) | YES | | NULL | |
+----------+-------------+------+-----+---------+----------------+
SELECT * FROM data;
+----+----------+
| id | code |
+----+----------+
| 1 | 123abc
| 2 | 234def
| 3 | 567ghi
| 4 | 890jkl
I would like to add a column to the table called timestamp, I am doing this with..
alter table data add timestamp VARCHAR(20);
But then my table looks like this...
desc data;
+-----------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| code | varchar(10) | YES | | NULL | |
| timestamp | varchar(20) | YES | | NULL | |
+-----------+-------------+------+-----+---------+----------------+
SELECT * FROM data;
+----+----------+-----------+
| id | code | timestamp |
+----+----------+-----------+
| NULL |
| NULL |
| NULL |
| NULL |
Where am I going wrong?

Answer 1

here you can see the backticks
alter table `data` add `timestamp` VARCHAR(20);
SAMPLE
MariaDB []> desc data;
+-------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------------------+------+-----+---------+----------------+
| id | int(11) unsigned | NO | PRI | NULL | auto_increment |
| e | enum('x1','x2','x3') | YES | | NULL | |
+-------+----------------------+------+-----+---------+----------------+
2 rows in set (0.01 sec)
MariaDB []> alter table `data` add `timestamp` VARCHAR(20);
Query OK, 0 rows affected (0.05 sec)
Records: 0 Duplicates: 0 Warnings: 0
MariaDB []> desc data;
+-----------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+----------------+
| id | int(11) unsigned | NO | PRI | NULL | auto_increment |
| e | enum('x1','x2','x3') | YES | | NULL | |
| timestamp | varchar(20) | YES | | NULL | |
+-----------+----------------------+------+-----+---------+----------------+
3 rows in set (0.01 sec)
Table Data
MariaDB [who]> select * from `data`;
+----+------+-----------+
| id | e | timestamp |
+----+------+-----------+
| 1 | x1 | NULL |
| 2 | x2 | NULL |
+----+------+-----------+
2 rows in set (0.00 sec)
MariaDB [who]>