Is there a way to convert Integer field into Varchar without losing data in MySQL?
You can use ALTER command to convert Integer into Varchar. Let us first create a table
mysql> create table DemoTable
(
UserId int,
UserFirstName varchar(20),
UserLastName varchar(20),
UserAge int
);
Query OK, 0 rows affected (0.73 sec)
Now check the description of table using DESC command:
mysql> desc DemoTable;
This will produce the following output −
+---------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+-------------+------+-----+---------+-------+
| UserId | int(11) | YES | | NULL | |
| UserFirstName | varchar(20) | YES | | NULL | |
| UserLastName | varchar(20) | YES | | NULL | |
| UserAge | int(11) | YES | | NULL | |
+---------------+-------------+------+-----+---------+-------+
4 rows in set (0.17 sec)
Now you can change the integer data type to varchar without losing data:
mysql> alter table DemoTable change UserId UserId varchar(20);
Query OK, 0 rows affected (1.35 sec)
Records: 0 Duplicates: 0 Warnings: 0
Check the table description:
mysql> desc DemoTable;
This will produce the following output −
+---------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------------+-------------+------+-----+---------+-------+
| UserId | varchar(20) | YES | | NULL | |
| UserFirstName | varchar(20) | YES | | NULL | |
| UserLastName | varchar(20) | YES | | NULL | |
| UserAge | int(11) | YES | | NULL | |
+---------------+-------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
Published on 29-Apr-2019 12:05:39
