mysql> create table test(a int,b char(20));
Query OK, 0 rows affected (0.09 sec)

mysql> desc test;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
2 rows in set (0.01 sec)




mysql> alter table test rename as test2;
Query OK, 0 rows affected (0.00 sec)

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
2 rows in set (0.01 sec)



mysql> alter table test2 add c int;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
| c     | int(11)  | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)


mysql> alter table test2 add d int after a;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| d     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
| c     | int(11)  | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)



mysql> alter table test2 drop d;
Query OK, 0 rows affected (0.02 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
| c     | int(11)  | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)



mysql> alter table test2 change c d char;
Query OK, 0 rows affected (0.02 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
| d     | char(1)  | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.01 sec)



mysql> alter table test2 change d d int;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> desc test2;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| a     | int(11)  | YES  |     | NULL    |       |
| b     | char(20) | YES  |     | NULL    |       |
| d     | int(11)  | YES  |     | NULL    |       |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)