How can I alter a user-defined table type in SQL Server ?
Here are simple steps that minimize tedium and don't require error-prone semi-automated scripts or pricey tools.
Keep in mind that you can generate DROP/CREATE statements for multiple objects from the Object Explorer Details window (when generated this way, DROP and CREATE scripts are grouped, which makes it easy to insert logic between Drop and Create actions):
If you have smaller projects where it might make sense to change the infrastructure architecture, consider eliminating user-defined table types. Entity Framework and similar tools allow you to move most, if not all, of your data logic to your code base where it's easier to maintain.