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3SELECTC.value(".","varchar(30)")FROM @x.nodes("/People/dongsheng/Info[@Name="Email"]") T(C)-- 方法4SELECTC.value("(Info[@Name="Email"])[1]","varchar(30)")FROM @x.nodes("/People/dongsheng") T(C)-- 方法5SELECTC.value("(dongsheng/Info[@Name="Email"])[1]","varchar(30)")FROM @x.nodes("/People") T(C)-- 方法6SELECTC.value(".","varchar(30)")FROM @x.nodes("/People/dongsheng/Info") T(C)WHERE C.value("(.[@Name="Email"])[1]","varchar(30)") IS NOT NULL-- 方法7SELECTC.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>"SELECTv.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1SELECTC.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("/Employees/Employee[@dept="IT"]/Info") T(C)/*NAME SEXQQ---------- ---------- --------------------dongsheng 男 5454545454土豆 女 5345454554*/--方法2SELECTC.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"]/*") T(C)/*NAME SEXQQ---------- ---------- --------------------dongsheng 男 5454545454土豆 女 5345454554*/--查询出IT部门type为Permanent的员工SELECTC.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 SEXQQ---------- ---------- --------------------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>"SELECTC.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>"SELECTC.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-------------------- ---------------------------- -----------------------------134*/--返回没个节点的属性值SELECTC.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") = 1SELECT "Exists" AS ResultELSESELECT "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")]") = 1SELECT "Exists" AS ResultELSESELECT "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 BEGINSELECT@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: " + @attNamePRINT "Attribute Value: " + @attValuePRINT ""-- increment the counter variableSELECT @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 BEGINSELECT@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 variableSELECT @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(SELECTC.value("local-name(.)","VARCHAR(20)") AS attrName,C.value(".","VARCHAR(20)") AS attrValueFROM @x.nodes("/*/*/*") T(C) --第三层) as p/*1001Email1dongsheng@xxyy.com1001Phone6789455461001QQ 365751001Addr36575*/
/* 解析XML存储过程*/ALTER PROCEDURE [dbo].[sp_ExportXml] @x xml , @layerstr nvarchar(max)ASDECLARE @sql nvarchar(max)BEGIN set arithabort onset @sql="select p.* FROM(SELECTC.value(""local-name(.)"",""VARCHAR(20)"") AS attrName,C.value(""."",""VARCHAR(20)"") AS attrValueFROM @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。