# Functions (MDX Syntax)

**THIS TOPIC APPLIES TO:**SQL Server (starting with 2008)Azure SQL DatabaseAzure SQL Data Warehouse Parallel Data Warehouse

Multidimensional Expressions (MDX) has several categories of intrinsic functions to perform certain operations. The following table lists the function categories that are available in MDX.

##### Note

For more information about individual functions, see MDX Function Reference (MDX).

Function Category | Description |
---|---|

Array functions | Provide arrays for use in stored procedures. For more information, see Using Stored Procedures (MDX). |

Dimension functions | Return a reference to a dimension from a hierarchy, level, or member. For more information, see Using Dimension, Hierarchy, and Level Functions. |

Hierarchy functions | Return a reference to a hierarchy from a level or member. For more information, see Using Dimension, Hierarchy, and Level Functions. |

Level functions | Return a reference to a level from a member, dimension, hierarchy, or from a string expression. For more information, see Using Dimension, Hierarchy, and Level Functions. |

Logical functions | Perform logical operations and comparisons on objects and expressions. For more information, see Using Logical Functions. |

Member functions | Return a reference to a member from other objects or from a string expression. For more information, see Using Member Functions. |

Numeric functions | Perform mathematical and statistical functions on objects and expressions. For more information, see Using Mathematical Functions. |

Set functions | Return a reference to a set from other objects or from a string expression. For more information, see Using Set Functions. |

String functions | Return string values from other objects or from the server. For more information, see Using String Functions. |

Tuple functions | Return a reference to a tuple from a set or from a string expression. For more information, see Using Tuple Functions. |

## Uses of Functions

Functions can be used or included in any MDX expression. Functions can also be nested (one function used inside another function).