---
title: "MDX Syntax Conventions (MDX) | Microsoft Docs"
ms.date: 06/04/2018
ms.prod: sql
ms.technology: analysis-services
ms.custom: mdx
ms.topic: reference
ms.author: owend
ms.reviewer: owend
author: minewiskan
---
# MDX Syntax Conventions (MDX)


  The diagrams for Multidimensional Expressions (MDX) syntax in the MDX Language Reference use these conventions.  
  
|Convention|Usage|  
|----------------|-----------|  
|*italic*|Indicates user-supplied arguments of MDX syntax.|  
|| (vertical bar)|Separates syntax items within brackets or braces. You can select only one of the items.|  
|`[ ]` (brackets)|Indicates optional syntax items. Do not type the brackets.|  
|[,] ...n|Indicates that the preceding item can be repeated any number of times. The items are sometimes separated by commas.|  
|\<label> ::=|Indicates the name for a block of syntax. This convention is used to group and label portions of lengthy syntax or a unit of syntax that can be used in more than one place within a statement. Each location in which the block of syntax can be used is indicated with the label enclosed in angle brackets: \<label>.|  
  
## See Also  
 [MDX Language Reference &#40;MDX&#41;](../mdx/mdx-language-reference-mdx.md)