To update the column size, you can use alter command. The syntax is as follows −
alter table yourTableName change yourColumnName yourColumnName data type;
To understand the above syntax, let us create a table. The query to create a table −
mysql> create table DataTruncated −> ( −> id int, −> Name varchar(5) −> ); Query OK, 0 rows affected (0.64 sec)
Look at the column ‘Name’ above, the column size is 5. Whenever we will give the size greater than 5 then MySQL gives the following error −
mysql> insert into DataTruncated values(101,'JohnSmith'); ERROR 1406 (22001): Data too long for column 'Name' at row 1
Now update the column size of column ‘Name’. The query is as follows −
mysql> alter table DataTruncated change Name Name varchar(200); Query OK, 0 rows affected (2.01 sec) Records: 0 Duplicates: 0 Warnings: 0
Insert the same record into the table. Now no error is visible since we updated the column size from 5 to 25 −
mysql> insert into DataTruncated values(101,'JohnSmith'); Query OK, 1 row affected (0.11 sec)
Display the records −
mysql> select *from DataTruncated;
The following is the output −
+------+-----------+ | id | Name | +------+-----------+ | 101 | JohnSmith | +------+-----------+ 1 row in set (0.00 sec)