sqlserver FOR XML查询参数RAW的实例

SQL SERVER中XML查询:FOR XML指定RAW

前言

在SQL SERVER中,XML查询可以指定RAW,AUTO,EXPLICIT,PATH。本文用一些实例介绍SQL SERVER中指定RAW的XML查询。

基础FOR XML查询

看实例:

with TestXml
as
(
    select 1 as id,'LeeWhoeeUniversity' as name
    union all
    select 2,'SQLSERVER中XML查询'
    union all
    select 3 ,'FOR XML'
)
select id,name from testxml for xml raw,type

运行后结果:

<row id="1" name="LeeWhoeeUniversity" />
<row id="2" name="SQLSERVER中XML查询" />
<row id="3" name="FOR XML" />

红色字体type可选,不会影响结果,只是影响数据类型。


指定 ELEMENTS


with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw,
elements

注意,第三行值改为NULL值进行测试。

结果:

<row>
  <id>1</id>
  <name>LeeWhoeeUniversity</name>
</row>
<row>
  <id>2</id>
  <name>SQLSERVER中XML查询</name>
</row>
<row>
  <id>3</id>
</row>

元素name在第三行没有出现,因为是NULL值。

但是我们可以用XSINIL生成NULL值的name元素。

如:

with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw,elements
XSINIL 
运行结果:

<row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <id>1</id>
  <name>LeeWhoeeUniversity</name>
</row>
<row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <id>2</id>
  <name>SQLSERVER中XML查询</name>
</row>
<row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <id>3</id>
  <name xsi:nil="true" />
</row>


使用XMLDATA和XMLSCHEMA


XMLDATA返回描述文档结构的 XML-DATA 架构。

如:

with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw,
XMLDATA  


结果:

<Schema name="Schema2" xmlns="urn:schemas-microsoft-com:xml-data" xmlns:dt="urn:schemas-microsoft-com:datatypes">
  <ElementType name="row" content="empty" model="closed">
    <AttributeType name="id" dt:type="i4" />
    <AttributeType name="name" dt:type="string" />
    <attribute type="id" />
    <attribute type="name" />
  </ElementType>
</Schema>
<row xmlns="x-schema:#Schema2" id="1" name="LeeWhoeeUniversity" />
<row xmlns="x-schema:#Schema2" id="2" name="SQLSERVER中XML查询" />
<row xmlns="x-schema:#Schema2" id="3" />


XML SCHEMA


通过指定 XMLSCHEMA 选项,您可以针对结果请求 XSD 架构:

with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw,
XMLSCHEMA   
结果:

<xsd:schema targetNamespace="urn:schemas-microsoft-com:sql:SqlRowSet2" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sqltypes="http://schemas.microsoft.com/sqlserver/2004/sqltypes" elementFormDefault="qualified">
  <xsd:import namespace="http://schemas.microsoft.com/sqlserver/2004/sqltypes" schemaLocation="http://schemas.microsoft.com/sqlserver/2004/sqltypes/sqltypes.xsd" />
  <xsd:element name="row">
    <xsd:complexType>
      <xsd:attribute name="id" type="sqltypes:int" use="required" />
      <xsd:attribute name="name">
        <xsd:simpleType>
          <xsd:restriction base="sqltypes:nvarchar" sqltypes:localeId="2052" sqltypes:sqlCompareOptions="IgnoreCase IgnoreKanaType IgnoreWidth">
            <xsd:maxLength value="12" />
          </xsd:restriction>
        </xsd:simpleType>
      </xsd:attribute>
    </xsd:complexType>
  </xsd:element>
</xsd:schema>
<row xmlns="urn:schemas-microsoft-com:sql:SqlRowSet2" id="1" name="LeeWhoeeUniversity" />
<row xmlns="urn:schemas-microsoft-com:sql:SqlRowSet2" id="2" name="SQLSERVER中XML查询" />
<row xmlns="urn:schemas-microsoft-com:sql:SqlRowSet2" id="3" />


您可以将目标命名空间 URI 指定为 FOR XML 中 XMLSCHEMA 的可选参数。


with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw,
XMLSCHEMA ('urn:http://blog.csdn.net/lihui_830501') 


结果:

<xsd:schema targetNamespace="urn:http://blog.csdn.net/lihui_830501" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sqltypes="http://schemas.microsoft.com/sqlserver/2004/sqltypes" elementFormDefault="qualified">
  <xsd:import namespace="http://schemas.microsoft.com/sqlserver/2004/sqltypes" schemaLocation="http://schemas.microsoft.com/sqlserver/2004/sqltypes/sqltypes.xsd" />
  <xsd:element name="row">
    <xsd:complexType>
      <xsd:attribute name="id" type="sqltypes:int" use="required" />
      <xsd:attribute name="name">
        <xsd:simpleType>
          <xsd:restriction base="sqltypes:nvarchar" sqltypes:localeId="2052" sqltypes:sqlCompareOptions="IgnoreCase IgnoreKanaType IgnoreWidth">
            <xsd:maxLength value="12" />
          </xsd:restriction>
        </xsd:simpleType>
      </xsd:attribute>
    </xsd:complexType>
  </xsd:element>
</xsd:schema>
<row xmlns="urn:http://blog.csdn.net/lihui_830501" id="1" name="LeeWhoeeUniversity" />
<row xmlns="urn:http://blog.csdn.net/lihui_830501" id="2" name="SQLSERVER中XML查询" />
<row xmlns="urn:http://blog.csdn.net/lihui_830501" id="3" />


检索二进制数据

像XMLDATA一样,在SQL中指定BINARY BASE64。


重命名 <row> 元素


with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml
raw ('myrow')

结果:

<myrow id="1" name="LeeWhoeeUniversity" />
<myrow id="2" name="SQLSERVER中XML查询" />
<myrow id="3" />


指定ELEMENTS的情况类同。


为 FOR XML 生成的 XML 指定根元素


with TestXml
as
(
    select 1 as id,N'LeeWhoeeUniversity' as name
    union all
    select 2,N'SQLSERVER中XML查询'
    union all
    select 3 ,null
)
select id,name from testxml for xml raw
,root('myroot')

结果:

<myroot>
  <row id="1" name="LeeWhoeeUniversity" />
  <row id="2" name="SQLSERVER中XML查询" />
  <row id="3" />
</myroot>


查询 XML 类型的列


 

  1.  
    declare @xml table(xid int,xname varchar(50),xmlcol xml);
  2.  
    insert into @xml select 1,'第一行','<myroot>
  3.  
    <row id="1" name="LeeWhoeeUniversity" />
  4.  
    <row id="2" name="SQLSERVER中XML查询" />
  5.  
    <row id="3" />
  6.  
    </myroot>'
  7.  
    insert into @xml select 2,'第二行','<myroot>
  8.  
    <row id="4" name="XML数据" />
  9.  
    <row id="5" name="FOR XML指定RAW" />
  10.  
    </myroot>'
  11.  
    select xid,xname,xmlcol.query('/myroot') from @xml for xml raw


 

结果:

<row xid="1" xname="第一行">
  <myroot>
    <row id="1" name="LeeWhoeeUniversity" />
    <row id="2" name="SQLSERVER中XML查询" />
    <row id="3" />
  </myroot>
</row>
<row xid="2" xname="第二行">
  <myroot>
    <row id="4" name="XML数据" />
    <row id="5" name="FOR XML指定RAW" />
  </myroot>
</row>



总结


以上对指定RAW的XML查询就介绍完了,下一篇文章将继续用实例介绍SQL SERVER中的XML查询:指定AUTO查询。
 
posted @ 2022-11-14 20:07  yclizq  阅读(143)  评论(0编辑  收藏  举报