INTRODUCTION SELECT * from people WHERE iq < shoe SQL:1999 syntax invalid in SQL Server SELECT * FROM people WHERE CAST(iq AS shoesize) < shoe SQL Server 2005 goes beyond previous versions in support of SQL:1999 distinct and complex user-defined types. Extended data types must be defined as .NET classes and cannot be defined in Transact-SQL, although they are accessible in T-SQL stored procedures, user-defined functions, and other procedural code. These classes (types) may have member functions that are accessible in T-SQL la SQL distinct types, and in addition they may have mutator functions that are usable in T-SQL UPDATE statements. In addition to enabling users to define distinct types based on a single built-in data type, SQL Server 2005 allows user-defined types to have multiple storage items (attributes). Such a user-defined data type is considered a complex type in SQL:1999. Once defined to the SQL Server catalog, the new type may be used as a column in a table. Variables of the type may be used in stored procedures, and the type s attributes and methods may be used in computed types and user-defined functions. Although we ll see how to define user-defined distinct and complex types in Chapter 5, Listing 1-5 shows an example of defining a user-defined complex type, ComplexNumber, and using it as a column in a table. Listing 1-5: Defining a User-Defined Type and Using It in a Table CREATE TYPE ComplexNumber EXTERNAL NAME SomeTypes:ComplexNumber GO CREATE TABLE Transforms( transform_id BIGINT, transform_input, ComplexNumber, transform_result ComplexNumber) GO After even a fundamental description, we should immediately point out that SQL Server complex types extend relational data types. The most common usage will not be to define object data types that might be defined in an object-oriented database, but to define new scalar types that extend the relational type system, such as the ComplexNumber type shown Note: If you are looking for good and high quality web space to host and run your application check Lunarwebhost Adult Web Hosting services

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