[From MSDN Magazine
The next version of SQL Server, code-named "Yukon," will offer enhanced support for user-defined types (UDTs). Because UDTs can be managed by the CLR, you can represent a wide variety of data structures to create types not possible with previous versions of SQL Server. With UDTs you can more precisely control the kind of data your type accepts, resulting in better data management. This article explores UDTs in "Yukon" and covers their design and implementation.
User-defined types (UDTs) are one of the new common language runtime (CLR) integration features in the next version of SQL Server, code-named "Yukon." UDTs in Yukon represent a significant advance from previous versions of SQL Server. SQL Server 2000, for example, supports alias types, which provide a simple way for users to redefine native types. Alias types are created using an existing data type that was defined the same way in multiple locations (tables, procedures, and so on). For example, a ZIP code could be used in multiple tables and as a parameter in multiple stored procedures. You could create a type named ZIP in the following manner...
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