Deleting or Dropping an Alias Data Type in SQL SERVER

Imagine you had created a custom data type for your database:

USE Northwind;
CREATE TYPE NaturalNumber FROM int;

If you don't need such a data type any more, to assist you with removing it, Transact-SQL provides thesp_droptype. Its syntax is:

sp_droptype [ @typename= ] 'type'

This procedure takes one argument as the name of the custom data type you want to delete. Here is an example of executing it:

sp_droptype NaturalNumber;

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