DROP DOMAIN domain-name 

DROP DOMAIN is prevented if the data type is used in a table column, or in a procedure or function argument. You must change data types on all columns defined using the domain to drop the data type. It is recommended that you use DROP DOMAIN rather than DROP DATATYPE, as DROP DOMAIN is the syntax used in the SQL/2008 standard. You cannot drop system-defined data types (such as MONEY or UNIQUEIDENTIFIERSTR) from a database.

Any user who owns the object, or has DBA authority, can execute the DROP DOMAIN statement.

Automatic commit. Clears the Results tab in the Results pane in Interactive SQL.

• CREATE DOMAIN statement
• ALTER DOMAIN statement

Drop the domain MyDomain from the database. If the domain does not exist, an error is returned.

DROP DOMAIN MyDomain;