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Changing Column Size
Changing the size of a column in MySQL is pretty easy. By using alter table and modify you are able to choose a column on a specified table and resize it. Learn how to resize a MySQL column.

How to Change a Column Name
If you have created a database and decide later that one of the column names you chose isn't exactly what you want, you can rename it. You do this using alter table and change. Together they can be used to rename a MySQL column.

Backup and Restore MySQL Databases
It is a good idea to backup your MySQL data occasionally as a precautionary measure. It is also a good idea to create a backup before making any major changes, incase something goes wrong and you need to revert to the unmodified version. Database backups can also be used to transfer your database from one server to another if you change web hosts.