SQL Server Functions
This section provides detailed documentation on the built-in functions available in the SQL Server Database Engine. Functions perform operations on one or more input values and return a single value.
Categories
Aggregate Functions
Perform calculations on a set of values and return a single value.
Date and Time Functions
Return or manipulate date and time values.
String Functions
Manipulate string values.
Numeric Functions
Perform mathematical operations on numeric values.
System Functions
Return information about the system or current context.
Mathematical Functions
Perform mathematical calculations like rounding, square roots, etc.
Security Functions
Return security-related information.
Ranking Functions
Assign a rank to each row within a partition of a result set.
JSON Functions
Process JSON data.
XML Functions
Process XML data.
Featured Functions
GETDATE()
Returns the current database system timestamp.
SUM()
Calculates the sum of values in a column.
LEFT()
Returns the left part of a character string.
ISNULL()
Replaces NULL with a specified replacement value.
COUNT()
Returns the number of items in a group.
FORMAT()
Formats a value and converts it to a string.
Learn More
For a complete list and syntax of all functions, refer to the full function reference.