You need to use the ALTER TABLE syntax to change the structure of an existing table. For example, you can add or delete columns, create or destroy indexes, change the type of existing columns, and much more with ALTER TABLE.
Step # 1: Login to mysql
Type the following command:mysql -u user -p databasename
Step 2: Delete column
First see table description:desc tableName
Use the following syntax at mysql>
ALTER TABLE tableName DROP columnName;
For example, see t1 table description, enter:
DESC t1;
Sample outputs:+-------+-------------+------+-----+---------+-------+Delete column c2, enter:
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| c1 | int(11) | YES | | NULL | |
| c2 | varchar(30) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
ALTER TABLE t1 DROP c2;Sample outputs:
DESC t1
+-------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| c1 | int(11) | YES | | NULL | |
+-------+---------+------+-----+---------+-------+
1 row in set (0.00 sec)
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