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Example: Requesting Schemas as Results Using the XMLDATA and XMLSCHEMA Options

The following query returns the XML-DATA schema that describes the document structure.

Example

USE AdventureWorks;
GO
SELECT ProductModelID, Name
FROM Production.ProductModel
WHERE ProductModelID=122 or ProductModelID=119
FOR XML RAW, XMLDATA
GO

This is the result:

<Schema name="Schema1" xmlns="urn:schemas-microsoft-com:xml-data" 
        xmlns:dt="urn:schemas-microsoft-com:datatypes">
  <ElementType name="row" content="empty" model="closed">
    <AttributeType name="ProductModelID" dt:type="i4" />
    <AttributeType name="Name" dt:type="string" />
    <attribute type="ProductModelID" />
    <attribute type="Name" />
  </ElementType>
</Schema>
<row xmlns="x-schema:#Schema1" ProductModelID="122" Name="All-Purpose Bike Stand" />
<row xmlns="x-schema:#Schema1" ProductModelID="119" Name="Bike Wash" />

Note

The <Schema> is declared as a namespace. To avoid namespace collisions when multiple XML-Data schemas are requested in different FOR XML queries, the namespace identifier, Schema1 in this example, changes with every query execution. The namespace identifier is made up of Scheman where n is an integer.

By specifying the XMLSCHEMA option, you can request the XSD schema for the result.

USE AdventureWorks;
GO
SELECT ProductModelID, Name
FROM Production.ProductModel
WHERE ProductModelID=122 or ProductModelID=119
FOR XML RAW, XMLSCHEMA
GO

This is the result:

<xsd:schema targetNamespace="urn:schemas-microsoft-com:sql:SqlRowSet1" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sqltypes="https://schemas.microsoft.com/sqlserver/2004/sqltypes" elementFormDefault="qualified">
  <xsd:import namespace="https://schemas.microsoft.com/sqlserver/2004/sqltypes" schemaLocation="https://schemas.microsoft.com/sqlserver/2004/sqltypes/sqltypes.xsd" />
  <xsd:element name="row">
    <xsd:complexType>
      <xsd:attribute name="ProductModelID" type="sqltypes:int" use="required" />
      <xsd:attribute name="Name" use="required">
        <xsd:simpleType sqltypes:sqlTypeAlias="[AdventureWorks].[dbo].[Name]">
          <xsd:restriction base="sqltypes:nvarchar" sqltypes:localeId="1033" sqltypes:sqlCompareOptions="IgnoreCase IgnoreKanaType IgnoreWidth" sqltypes:sqlSortId="52">
            <xsd:maxLength value="50" />
          </xsd:restriction>
        </xsd:simpleType>
      </xsd:attribute>
    </xsd:complexType>
  </xsd:element>
</xsd:schema>
<row xmlns="urn:schemas-microsoft-com:sql:SqlRowSet1" ProductModelID="122" Name="All-Purpose Bike Stand" />
<row xmlns="urn:schemas-microsoft-com:sql:SqlRowSet1" ProductModelID="119" Name="Bike Wash" />

You can specify the target namespace URI as an optional argument to XMLSCHEMA in FOR XML. This returns the specified target namespace in the schema. This target namespace remains the same every time you execute the query. For example, the following modified version of the previous query includes the namespace URI, 'urn:example.com', as an argument.

USE AdventureWorks;
GO
SELECT ProductModelID, Name
FROM Production.ProductModel
WHERE ProductModelID=122 or ProductModelID=119
FOR XML RAW, XMLSCHEMA ('urn:example.com')
GO

This is the result:

<xsd:schema targetNamespace="urn:example.com" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sqltypes="https://schemas.microsoft.com/sqlserver/2004/sqltypes" elementFormDefault="qualified">
  <xsd:import namespace="https://schemas.microsoft.com/sqlserver/2004/sqltypes" schemaLocation="https://schemas.microsoft.com/sqlserver/2004/sqltypes/sqltypes.xsd" />
  <xsd:element name="row">
    <xsd:complexType>
      <xsd:attribute name="ProductModelID" type="sqltypes:int" use="required" />
      <xsd:attribute name="Name" use="required">
        <xsd:simpleType sqltypes:sqlTypeAlias="[AdventureWorks].[dbo].[Name]">
          <xsd:restriction base="sqltypes:nvarchar" sqltypes:localeId="1033" sqltypes:sqlCompareOptions="IgnoreCase IgnoreKanaType IgnoreWidth" sqltypes:sqlSortId="52">
            <xsd:maxLength value="50" />
          </xsd:restriction>
        </xsd:simpleType>
      </xsd:attribute>
    </xsd:complexType>
  </xsd:element>
</xsd:schema>
<row xmlns="urn:example.com" ProductModelID="122" Name="All-Purpose Bike Stand" />
<row xmlns="urn:example.com" ProductModelID="119" Name="Bike Wash" />

See Also

Reference

Using RAW Mode