SQL Server解析XML数据的方法详解

本文实例讲述了SQL Server解析XML数据的方法。分享给大家供大家参考，具体如下：

--5.读取XML--下面为多种方法从XML中读取EMAILDECLARE @x XMLSELECT @x = '<People>  <dongsheng>    <Info Name="Email">dongsheng@xxyy.com</Info>    <Info Name="Phone">678945546</Info>    <Info Name="qq">36575</Info>  </dongsheng></People>'-- 方法1SELECT @x.value('data(/People/dongsheng/Info[@Name="Email"])[1]', 'varchar(30)')-- 方法2SELECT @x.value('(/People/dongsheng/Info[@Name="Email"])[1]', 'varchar(30)')-- 方法3SELECT  C.value('.','varchar(30)')FROM @x.nodes('/People/dongsheng/Info[@Name="Email"]') T(C)-- 方法4SELECT  C.value('(Info[@Name="Email"])[1]','varchar(30)')FROM @x.nodes('/People/dongsheng') T(C)-- 方法5SELECT  C.value('(dongsheng/Info[@Name="Email"])[1]','varchar(30)')FROM @x.nodes('/People') T(C)-- 方法6SELECT  C.value('.','varchar(30)')FROM @x.nodes('/People/dongsheng/Info') T(C)WHERE C.value('(.[@Name="Email"])[1]','varchar(30)') IS NOT NULL-- 方法7SELECT  C.value('.','varchar(30)')FROM @x.nodes('/People/dongsheng/Info') T(C)WHERE C.exist('(.[@Name="Email"])[1]') = 1--6.Reading values from an XML variableDECLARE @x XMLSELECT @x ='<Peoples>  <People Name="tudou" Sex="女" />  <People Name="choushuigou" Sex="女"/>  <People Name="dongsheng" Sex="男" /></Peoples>'SELECT  v.value('@Name[1]','VARCHAR(20)') AS Name,  v.value('@Sex[1]','VARCHAR(20)') AS SexFROM @x.nodes('/Peoples/People') x(v)--7.多属性过滤DECLARE @x XMLSELECT @x = '<Employees> <Employee id="1234" dept="IT" type="合同工">  <Info NAME="dongsheng" SEX="男" QQ="5454545454"/> </Employee> <Employee id="5656" dept="IT" type="临时工">  <Info NAME="土豆" SEX="女" QQ="5345454554"/> </Employee> <Employee id="3242" dept="市场" type="合同工">  <Info NAME="choushuigou" SEX="女" QQ="54543545"/> </Employee></Employees>'--查询dept为IT的人员信息  --方法1  SELECT    C.value('@NAME[1]','VARCHAR(10)') AS NAME,    C.value('@SEX[1]','VARCHAR(10)') AS SEX,    C.value('@QQ[1]','VARCHAR(20)') AS QQ  FROM @x.nodes('/Employees/Employee[@dept="IT"]/Info') T(C)  /*  NAME   SEX    QQ  ---------- ---------- --------------------  dongsheng 男     5454545454  土豆   女     5345454554  */  --方法2  SELECT    C.value('@NAME[1]','VARCHAR(10)') AS NAME,    C.value('@SEX[1]','VARCHAR(10)') AS SEX,    C.value('@QQ[1]','VARCHAR(20)') AS QQ  FROM @x.nodes('//Employee[@dept="IT"]/*') T(C)  /*  NAME   SEX    QQ  ---------- ---------- --------------------  dongsheng 男     5454545454  土豆   女     5345454554  */--查询出IT部门type为Permanent的员工SELECT  C.value('@NAME[1]','VARCHAR(10)') AS NAME,  C.value('@SEX[1]','VARCHAR(10)') AS SEX,  C.value('@QQ[1]','VARCHAR(20)') AS QQFROM @x.nodes('//Employee[@dept="IT"][@type="合同工"]/*') T(C)/*  NAME   SEX    QQ  ---------- ---------- --------------------  dongsheng 男     5454545454*/--12.从XML变量中删除元素DECLARE @x XMLSELECT @x = '<Peoples> <People>   <NAME>土豆</NAME>   <SEX>男</SEX>   <QQ>5345454554</QQ> </People></Peoples>'SET @x.modify('  delete (/Peoples/People/SEX)[1]' )SELECT @x/*<Peoples> <People>  <NAME>土豆</NAME>  <QQ>5345454554</QQ> </People></Peoples>*/--19.读取指定变量元素的值DECLARE @x XMLSELECT @x = '<Peoples> <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX>   <QQ>423545</QQ> </People> <People>   <NAME>土豆</NAME>   <SEX>男</SEX>   <QQ>123133</QQ> </People> <People>   <NAME>choushuigou</NAME>   <SEX>女</SEX>   <QQ>54543545</QQ> </People></Peoples>'DECLARE @ElementName VARCHAR(20)SELECT @ElementName = 'NAME'SELECT c.value('.','VARCHAR(20)') AS NAMEFROM @x.nodes('/Peoples/People/*[local-name()=sql:variable("@ElementName")]') T(C)/*NAME--------------------dongsheng土豆choushuigou*/--20使用通配符读取元素值--读取根元素的值DECLARE @x1 XMLSELECT @x1 = '<People>dongsheng</People>'SELECT @x1.value('(/*/text())[1]','VARCHAR(20)') AS People --星号*代表一个元素/*People--------------------dongsheng*/--读取第二层元素的值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX>   <QQ>423545</QQ> </People>'SELECT  @x.value('(/*/*/text())[1]','VARCHAR(20)') AS NAME/*NAME--------------------dongsheng*/--读取第二个子元素的值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX>   <QQ>423545</QQ> </People>'SELECT  @x.value('(/*/*/text())[2]','VARCHAR(20)') AS SEX/*SEX--------------------男*/--读取所有第二层子元素值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX>   <QQ>423545</QQ> </People>'SELECT  C.value('.','VARCHAR(20)') AS valueFROM @x.nodes('/*/*') T(C)/*value--------------------dongsheng男423545*/--21.使用通配符读取元素名称DECLARE @x XMLSELECT @x = '<People>dongsheng</People>'SELECT  @x.value('local-name(/*[1])','VARCHAR(20)') AS ElementName/*ElementName--------------------People*/--读取根下第一个元素的名称和值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX> </People>'SELECT  @x.value('local-name((/*/*)[1])','VARCHAR(20)') AS ElementName,  @x.value('(/*/*/text())[1]','VARCHAR(20)') AS ElementValue/*ElementName     ElementValue-------------------- --------------------NAME         dongsheng*/--读取根下第二个元素的名称和值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX> </People>'SELECT  @x.value('local-name((/*/*)[2])','VARCHAR(20)') AS ElementName,  @x.value('(/*/*/text())[2]','VARCHAR(20)') AS ElementValue/*ElementName     ElementValue-------------------- --------------------SEX         男*/--读取根下所有的元素名称和值DECLARE  @x XMLSELECT @x = ' <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX> </People>'SELECT  C.value('local-name(.)','VARCHAR(20)') AS ElementName,  C.value('.','VARCHAR(20)') AS ElementValueFROM @x.nodes('/*/*') T(C)/*ElementName     ElementValue-------------------- --------------------NAME         dongshengSEX         男*/---22.查询元素数量--如下Peoples根节点下有个People子节点。DECLARE @x XMLSELECT @x = '<Peoples> <People>   <NAME>dongsheng</NAME>   <SEX>男</SEX> </People> <People>   <NAME>土豆</NAME>   <SEX>男</SEX> </People> <People>   <NAME>choushuigou</NAME>   <SEX>女</SEX> </People></Peoples>'SELECT  @x.value('count(/Peoples/People)','INT') AS Children/*Children-----------3*/--如下Peoples根节点下第一个子节点People下子节点的数量SELECT  @x.value('count(/Peoples/People[1]/*)','INT') AS Children/*Children-----------2*/--某些时候我们可能不知道根节点和子节点的名称，可以用通配符来代替。SELECT  @x.value('count(/*/*)','INT') AS ChildrenOfRoot,     @x.value('count(/*/*[1]/*)','INT') AS ChildrenOfFirstChildElement/*ChildrenOfRoot ChildrenOfFirstChildElement-------------- ---------------------------3       2*/--23.查询属性的数量DECLARE @x XMLSELECT @x = '<Employees dept="IT">  <Employee NAME="dongsheng" SEX="男" QQ="5454545454"/>  <Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/></Employees>'--查询跟节点的属性数量SELECT  @x.value('count(/Employees/@*)','INT') AS AttributeCountOfRoot/*AttributeCountOfRoot--------------------1*/--第一个Employee节点的属性数量SELECT  @x.value('count(/Employees/Employee[1]/@*)','INT') AS AttributeCountOfFirstElement/*AttributeCountOfFirstElement----------------------------3*/--第二个Employee节点的属性数量SELECT  @x.value('count(/Employees/Employee[2]/@*)','INT') AS AttributeCountOfSeconfElement/*AttributeCountOfSeconfElement-----------------------------4*/--如果不清楚节点名称可以用*通配符代替SELECT  @x.value('count(/*/@*)','INT') AS AttributeCountOfRoot    ,@x.value('count(/*/*[1]/@*)','INT') AS AttributeCountOfFirstElement    ,@x.value('count(/*/*[2]/@*)','INT') AS AttributeCountOfSeconfElement/*AttributeCountOfRoot AttributeCountOfFirstElement AttributeCountOfSeconfElement-------------------- ---------------------------- -----------------------------1          3              4*/--返回没个节点的属性值SELECT  C.value('count(./@*)','INT') AS AttributeCountFROM @x.nodes('/*/*') T(C)/*AttributeCount--------------34*/--24.返回给定位置的属性值或者名称DECLARE @x XMLSELECT @x = '<Employees dept="IT">  <Employee NAME="dongsheng" SEX="男" QQ="5454545454"/>  <Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/></Employees>'--返回第一个Employee节点的第一个位置的属性值SELECT  @x.value('(/Employees/Employee[1]/@*[position()=1])[1]','VARCHAR(20)') AS AttValue/*AttValue--------------------dongsheng*/--返回第二个Employee节点的第四个位置的属性值SELECT  @x.value('(/Employees/Employee[2]/@*[position()=4])[1]','VARCHAR(20)') AS AttValue/*AttValue--------------------13954697895*/--返回第一个元素的第三个属性值SELECT  @x.value('local-name((/Employees/Employee[1]/@*[position()=3])[1])','VARCHAR(20)') AS AttName/*AttName--------------------QQ*/--返回第二个元素的第四个属性值SELECT  @x.value('local-name((/Employees/Employee[2]/@*[position()=4])[1])','VARCHAR(20)') AS AttName/*AttName--------------------TEL*/--通过变量传递位置返回属性值DECLARE @Elepos INT,@Attpos INTSELECT @Elepos=2,@Attpos = 3SELECT  @x.value('local-name((/Employees/Employee[sql:variable("@Elepos")]/@*[position()=sql:variable("@Attpos")])[1])','VARCHAR(20)') AS AttName/*AttName--------------------QQ*/--25.判断是XML中否存在相应的属性DECLARE  @x XMLSELECT @x = '<Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/>'IF @x.exist('/Employee/@NAME') = 1  SELECT 'Exists' AS ResultELSE  SELECT 'Does not exist' AS Result/*Result------Exists*/--传递变量判断是否存在DECLARE  @x XMLSELECT @x = '<Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/>'DECLARE @att VARCHAR(20)SELECT @att = 'QQ'IF @x.exist('/Employee/@*[local-name()=sql:variable("@att")]') = 1  SELECT 'Exists' AS ResultELSE  SELECT 'Does not exist' AS Result/*Result------Exists*/--26.循环遍历元素的所有属性DECLARE  @x XMLSELECT @x = '<Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/>'DECLARE  @cnt INT,  @totCnt INT,  @attName VARCHAR(30),  @attValue VARCHAR(30)SELECT  @cnt = 1,  @totCnt = @x.value('count(/Employee/@*)','INT')--获得属性总数量-- loopWHILE @cnt <= @totCnt BEGIN  SELECT    @attName = @x.value(      'local-name((/Employee/@*[position()=sql:variable("@cnt")])[1])',      'VARCHAR(30)'),    @attValue = @x.value(      '(/Employee/@*[position()=sql:variable("@cnt")])[1]',      'VARCHAR(30)')  PRINT 'Attribute Position: ' + CAST(@cnt AS VARCHAR)  PRINT 'Attribute Name: ' + @attName  PRINT 'Attribute Value: ' + @attValue  PRINT ''  -- increment the counter variable  SELECT @cnt = @cnt + 1END/*Attribute Position: 1Attribute Name: NAMEAttribute Value: 土豆Attribute Position: 2Attribute Name: SEXAttribute Value: 女Attribute Position: 3Attribute Name: QQAttribute Value: 5345454554Attribute Position: 4Attribute Name: TELAttribute Value: 13954697895*/--27.返回指定位置的子元素DECLARE @x XMLSELECT @x = '<Employees dept="IT">  <Employee NAME="dongsheng" SEX="男" QQ="5454545454"/>  <Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/></Employees>'SELECT @x.query('(/Employees/Employee)[1]')/*<Employee NAME="dongsheng" SEX="男" QQ="5454545454" />*/SELECT @x.query('(/Employees/Employee)[position()=2]')/*<Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895" />*/--通过变量获取指定位置的子元素DECLARE @i INTSELECT @i = 2SELECT @x.query('(/Employees/Employee)[sql:variable("@i")]')--orSELECT @x.query('(/Employees/Employee)[position()=sql:variable("@i")]')/*<Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895" />*/--28.循环遍历获得所有子元素DECLARE @x XMLSELECT @x = '<Employees dept="IT">  <Employee NAME="dongsheng" SEX="男" QQ="5454545454"/>  <Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/></Employees>'DECLARE  @cnt INT,  @totCnt INT,  @child XML-- counter variablesSELECT  @cnt = 1,  @totCnt = @x.value('count(/Employees/Employee)','INT')-- loopWHILE @cnt <= @totCnt BEGIN  SELECT    @child = @x.query('/Employees/Employee[position()=sql:variable("@cnt")]')  PRINT 'Processing Child Element: ' + CAST(@cnt AS VARCHAR)  PRINT 'Child element: ' + CAST(@child AS VARCHAR(100))  PRINT ''  -- incremet the counter variable  SELECT @cnt = @cnt + 1END/*Processing Child Element: 1Child element: <Employee NAME="dongsheng" SEX="男" QQ="5454545454"/>Processing Child Element: 2Child element: <Employee NAME="土豆" SEX="女" QQ="5345454554" TEL="13954697895"/>

SQL Server 中对XML数据的五种基本操作

1.xml.exist
输入为XQuery表达式，返回0，1或是Null。0表示不存在，1表示存在，Null表示输入为空
2.xml.value
输入为XQuery表达式，返回一个SQL Server标量值
3.xml.query
输入为XQuery表达式，返回一个SQL Server XML类型流
4.xml.nodes
输入为XQuery表达式，返回一个XML格式文档的一列行集
5.xml.modify

使用XQuery表达式对XML的节点进行insert , update 和 delete 操作。

下面通过例子对上面的五种操作进行说明：

declare @XMLVar xml = '<catalog>    <book category="ITPro">       <title>Windows Step By Step</title>       <author>Bill Zack</author>       <price>49.99</price>    </book>    <book category="Developer">       <title>Developing ADO .NET</title>       <author>Andrew Brust</author>       <price>39.93</price>    </book>    <book category="ITPro">       <title>Windows Cluster Server</title>       <author>Stephen Forte</author>       <price>59.99</price>    </book></catalog>'

1. xml.exist

select @XMLVar.exist('/catalog/book')-----返回1select @XMLVar.exist('/catalog/book/@category')-----返回1select @XMLVar.exist('/catalog/book1')-----返回0set @XMLVar = nullselect @XMLVar.exist('/catalog/book')-----返回null

2.xml.value

select @XMLVar.value('/catalog[1]/book[1]','varchar(MAX)')select @XMLVar.value('/catalog[1]/book[2]/@category','varchar(MAX)')select @XMLVar.value('/catalog[2]/book[1]','varchar(MAX)')

结果集为：
Windows Step By StepBill Zack49.99 Developer NULL
3.xml.query

select @XMLVar.query('/catalog[1]/book')select @XMLVar.query('/catalog[1]/book[1]')select @XMLVar.query('/catalog[1]/book[2]/author')

结果集分别为：

<book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price></book><book category="Developer"> <title>Developing ADO .NET</title> <author>Andrew Brust</author> <price>39.93</price></book><book category="ITPro"> <title>Windows Cluster Server</title> <author>Stephen Forte</author> <price>59.99</price></book><book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price></book><author>Andrew Brust</author>

4.xml.nodes

select T.c.query('.') as result from @XMLVar.nodes('/catalog/book') as T(c)select T.c.query('title') as result from @XMLVar.nodes('/catalog/book') as T(c)

结果集分别为：

<book category="ITPro"><title>Windows Step By Step</title><author>Bill …………<book category="Developer"><title>Developing ADO .NET</title><author>Andrew …………<book category="ITPro"><title>Windows Cluster Server</title><author>Stephen …………<title>Windows Step By Step</title><title>Developing ADO .NET</title><title>Windows Cluster Server</title>

set ARITHABORT onDECLARE @x XMLSELECT @x = '<Peoples><People>    <Email>1dongsheng@xxyy.com</Email>    <Phone>678945546</Phone>    <QQ>36575</QQ>    <Addr>36575</Addr></People></Peoples>'-- 方法1select 1001 as peopleId, p.* FROM(SELECT  C.value('local-name(.)','VARCHAR(20)') AS attrName,  C.value('.','VARCHAR(20)') AS attrValueFROM @x.nodes('/*/*/*') T(C) --第三层) as p/*1001  Email  1dongsheng@xxyy.com1001  Phone  6789455461001  QQ 365751001  Addr  36575*/

/* 解析XML存储过程*/ALTER PROCEDURE [dbo].[sp_ExportXml] @x xml , @layerstr nvarchar(max)AS  DECLARE @sql nvarchar(max)BEGIN   set arithabort on    set @sql='select p.* FROM(    SELECT        C.value(''local-name(.)'',''VARCHAR(20)'') AS attrName,        C.value(''.'',''VARCHAR(20)'') AS attrValue    FROM @xmlParas.nodes('''+@layerstr+''') T(C)    ) as p'  --print @sql   EXECUTE sp_executesql @sql, N'@xmlParas as xml',@xmlParas=@xEND

DECLARE @x XMLSELECT @x ='<Peoples><People>    <Email>1dongsheng@xxyy.com</Email>    <Phone>678945546</Phone>    <QQ>36575</QQ>    <Addr>36575</Addr></People></Peoples>'EXECUTE sp_ExportXml @x,'/*/*/*'

希望本文所述对大家SQL Server数据库程序设计有所帮助。