What is the SQL to change the field length of a table column in SQL Server

Question

What is the SQL to make a field go from nvarchar(50) to nvarchar(250)?

When I try to change it through the SQL Server Management Studio, it doesn't allow me to do it, so I figured I would try SQL directly instead of using the GUI.

Answer 1

Alter table tblname ALTER Column colname nvarchar(250) [NOT] NULL

If NULL / NOT NULL is not specified the column will become Nullable irrespective of what ever the original specification was.

Answer 2

ALTER TABLE MyTable
ALTER COLUMN MyColumn varchar(NewSize)