# SQL Function Reference¶

These topics provide reference information for the system-defined functions.

Summary of Functions — combined summary of all system-defined functions. Can be used as a quick-reference.

All Functions (Alphabetical) — alphabetical list of all system-defined functions (scalar, aggregate, table, etc.).

Scalar Functions — functions that take a single row/value as input and return a single value:

String Functions (Regular Expressions) — regular expression (search) functions

Aggregate Functions — functions that take multiple rows/values as input and return a single value.

Window Functions — subset of aggregate functions that can operate on a subset of rows.

Table Functions — functions that return results in tabular format.

System Functions — functions that perform control operations or return system-level information.