TSQL Built-in Functions

Built-in Functions (T-SQL)

Function	Description
Rowset Functions	Return an object that can be used like table references in an SQL statement.
Aggregate Functions	Operate on a collection of values but return a single, summarizing value.
Ranking Functions	Return a ranking value for each row in a partition.
Scalar Functions	Operate on a single value and then return a single value. Scalar functions can be used wherever an expression is valid.

 
Rowset Functions (Transact-SQL)

OPENDATASOURCE	OPENROWSET
OPENQUERY	OPENXML

Aggregate Functions

AVG	MIN
CHECKSUM_AGG	SUM
COUNT	STDEV
COUNT_BIG	STDEVP
GROUPING	VAR
GROUPING_ID	VARP
MAX

SQL Server provides many built-in functions and also provide you ability to create user-defined functions. The categories of built-in functions are listed.

SQL Server 2012

The following rowset functions return an object that can be used in place of a table reference in a Transact-SQL statement.

Aggregate functions perform a calculation on a set of values and return a single value. Except for COUNT, aggregate functions ignore null values. Aggregate functions are frequently used with the GROUP BY clause of the SELECT statement.

All aggregate functions are deterministic. This means aggregate functions return the same value any time that they are called by using a specific set of input values.The OVER clause may follow all aggregate functions except GROUPING and GROUPING_ID.

Aggregate functions can be used as expressions only in the following:

·         The select list of a SELECT statement (either a subquery or an outer query).

·         A HAVING clause.

Transact-SQL provides the following aggregate functions:

AVG
MIN
CHECKSUM_AGG
SUM
COUNT
STDEV
COUNT_BIG
STDEVP
GROUPING
VAR
GROUPING_ID
VARP
MAX