Accessing and manipulating data stored in SQL Server typically involves issuing commands, queries, and other instructions in Transact-SQL (T-SQL), Microsoft’s extension of the Structured Query Language (SQL), a standardized language for accessing and manipulating data in relational database management systems. T-SQL supplies several important capabilities to database developers:

• A set of Data Definition Language (DDL) commands that are used to create, define, and modify the actual databases on a SQL Server and the tables and data types they contain
• A set of Data Manipulation Language (DML) commands for reading and modifying data contained in the tables
• Control statements (IF-ELSE blocks, for instance) for managing execution flow
• Various operators and functions for computational tasks, such as mathematical and string operations.

For server-side programming tasks, developers group T-SQL commands into two primary types of functions: stored procedures and triggers. Stored procedures typically encapsulate complex data access or update operations (for example, handling all database updates associated with a business operation, such as hiring or firing an employee), whereas triggers “fire” when an attempt is made to change data in a database (triggers are most commonly used to maintain integrity and consistency across a database’s constituent tables).

Prior to Yukon, accessing and manipulating data stored in SQL Server primarily involved issuing commands, queries, and other instructions in Transact-SQL (T-SQL). T-SQL supplies several important capabilities to database developers:

• A set of Data Definition Language (DDL) commands that are used to create, define, and modify the actual databases on a SQL Server and the tables and data types they contain
• A set of Data Manipulation Language (DML) commands for reading and modifying data contained in the tables
• Control statements (IF-ELSE blocks, for instance) for managing execution flow; and various operators and functions for computational tasks, such as mathematical and string operations.

For server-side programming tasks, developers group T-SQL commands into two primary types of functions: stored procedures and triggers. Stored procedures typically encapsulate a data access or update query (for example, returning a subset of rows from a data table to a calling application), whereas triggers take some action when an attempt is made to change data in a database (for example, performing a validation when an attempt is made to insert a row in a table).