SQL Server - How to Alter Multiple tables in a database using a single SQL Query

Hi,
I have 250+ tables in my particular database, and i want to alter all the tables using a single query.
Suppose i want to add a column Total_Definition to all the tables of my database and i want to achieve the same using a single SQL Query.
Is it possible in SQL to Alter Multiple tables using one query.
If yes please guide at the earliest.

No, you have to use individual ALTER TABLE statements.  There is nothing that says you can't batch all of these up in one script file.