tsql - How do you change the datatype of a column in SQL Server?

Question

I am trying to change a column from a varchar(50) to a nvarchar(200). What is the SQL command to alter this table?

Answer 1

ALTER TABLE TableName 
ALTER COLUMN ColumnName NVARCHAR(200) [NULL | NOT NULL]

EDIT As noted NULL/NOT NULL should have been specified, see Rob's answer as well.