October 2015 Summaries

Reusability is a key principle in software development, but it can be challenging to achieve when writing T-SQL. User Defined Table Types (UDTTs) and Table Valued Functions (TVFs) are two objects available in SQL Server that can help improve reusability. UDTTs act as templates for tables created in memory, while TVFs return result sets instead of scalar values. Together, these objects enable more programmatic thinking when writing T-SQL statements and allow functions to accept and return data types that the calling process can understand. Additionally, using results sets instead of scalar values does not negatively impact performance.