---
title: "XQuery Basics | Microsoft Docs"
description: Learn the fundamentals of the XQuery language including, sequence and QNames, expression context, atomization, type system, error handling, and comments.
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ms.date: "03/17/2017"
ms.prod: sql
ms.prod_service: sql
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ms.technology: xml
ms.topic: "language-reference"
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  - "XML"
helpviewer_keywords: 
  - "XQuery, about XQuery"
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author: "rothja"
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---
# XQuery Basics
[!INCLUDE[tsql-appliesto-ss2012-xxxx-xxxx-xxx-md](../includes/tsql-appliesto-ss2012-xxxx-xxxx-xxx-md.md)]

  This section describes the fundamentals of XQuery.  
  
## In This Section  
 [Sequence and QNames (XQuery)](../xquery/sequence-and-qnames-xquery.md)  
 Describes sequence and also QNames and predefined namespaces.  
  
 [Expression Context and Query Evaluation (XQuery)](../xquery/expression-context-and-query-evaluation-xquery.md)  
 Describes the two contexts in which XQuery is evaluated. These two contexts are static and dynamic.  
  
 [Atomization (XQuery)](../xquery/atomization-xquery.md)  
 Describes atomization, which is a process of extracting the typed value of an item.  
  
 [Effective Boolean Value (XQuery)](../xquery/effective-boolean-value-xquery.md)  
 Describes the effective Boolean value. This value can be computed for expressions that return a single Boolean value, a node sequence, or an empty sequence.  
  
 [Type System (XQuery)](../xquery/type-system-xquery.md)  
 Describes the XQuery type system with various predefined types. XQuery is a strongly typed language for schema types and a weakly typed language for untyped data.  
  
 [Error Handling (XQuery)](../xquery/error-handling-xquery.md)  
 Describes the handling of static, dynamic, and type errors in XQuery.  
  
 [Comments in XQuery](../xquery/comments-in-xquery.md)  
 Describes how to add comments in XQuery by using the "`(:`" and "`:)`" delimiters  
  
 [XQuery and Static Typing](../xquery/xquery-and-static-typing.md)  
 Describes XQuery in [!INCLUDE[ssNoVersion](../includes/ssnoversion-md.md)] as a statically typed language  
  
## See Also  
 [XQuery Language Reference (SQL Server)](../xquery/xquery-language-reference-sql-server.md)