The Usage section of the alter table command has been revised. Replace the section titled “Restrictions for modifying text and image columns” with the following:
You can only add text or image columns that accept null values.
To add a text or image column so it contains only non-null values, first add a column that only accepts null values and then update it to the non-null values.
You can modify a column from text datatype only to the following datatypes:
[n]char
[n]varchar
unichar
univarchar
nchar
nvarchar
You can modify a column from image datatype only to binary or varbinary.
You cannot add a new text or image column and then drop an existing text or image column in the same statement.
You cannot modify a column to either text or image datatype.
