一般来说,您需要在问题中添加更多细节......所以这应该足以理解您可能需要定义的其他内容以及如何定义。我将通过说明假定的学生/地址关系来解决理解如何定义主键/外键所需的内容。
首先,您需要定义这些约束成立的上下文。在我修改后的 XSD 中,我称它为“世界”。
<?xml version="1.0" encoding="utf-8" ?>
<!-- XML Schema generated by QTAssistant/XSD Module (http://www.paschidev.com) -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="World">
<xs:complexType>
<xs:sequence>
<xs:element ref="Student" maxOccurs="unbounded"/>
<xs:element ref="Address" minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
<xs:key name="PKStudents">
<xs:selector xpath="Student/StudentID"/>
<xs:field xpath="."/>
</xs:key>
<xs:key name="PKAddresses">
<xs:selector xpath="Address/AddressID"/>
<xs:field xpath="."/>
</xs:key>
<xs:keyref name="FKStudentToAddress" refer="PKAddresses">
<xs:selector xpath="Student/AddressID"/>
<xs:field xpath="."/>
</xs:keyref>
</xs:element>
<xs:element name="Student">
<xs:complexType>
<xs:sequence>
<xs:element name="Title" type="xs:string"/>
<xs:element name="FirstName" type="xs:string"/>
<xs:element name="LastName" type="xs:string"/>
<xs:element name="Dateborn" type="xs:date"/>
<xs:element name="Gender" type="xs:string"/>
<xs:element name="StudentID" type="xs:string"/>
<xs:element name="AddressID" type="xs:string" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="Address">
<xs:complexType>
<xs:sequence>
<xs:element name="AddressID" type="xs:string"/>
<xs:element name="Street" type="xs:string"/>
<xs:element name="City" type="xs:string"/>
<xs:element name="Province" type="xs:string" minOccurs="0"/>
<xs:element name="Country" type="xs:date" minOccurs="0"/>
<xs:element name="PostalCode" type="xs:string" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
然后像这样的 XML 将通过或失败,这取决于您对 StudentID 和 AddressID 字段中的值执行的操作。
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<!-- Sample XML generated by QTAssistant (http://www.paschidev.com) -->
<World xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Student>
<Title>Title1</Title>
<FirstName>FirstName1</FirstName>
<LastName>LastName1</LastName>
<Dateborn>1900-01-01</Dateborn>
<Gender>Gender1</Gender>
<StudentID>StudentID1</StudentID>
<AddressID>AddressID1</AddressID>
</Student>
<Student>
<Title>Title1</Title>
<FirstName>FirstName1</FirstName>
<LastName>LastName1</LastName>
<Dateborn>1900-01-01</Dateborn>
<Gender>Gender1</Gender>
<StudentID>StudentID2</StudentID>
<AddressID>AddressID1</AddressID>
</Student>
<Address>
<AddressID>AddressID1</AddressID>
<Street>Street1</Street>
<City>City1</City>
<Province>Province1</Province>
<Country>1900-01-01</Country>
<PostalCode>PostalCode1</PostalCode>
</Address>
<Address>
<AddressID>AddressID2</AddressID>
<Street>Street1</Street>
<City>City1</City>
<Province>Province1</Province>
<Country>1900-01-01</Country>
<PostalCode>PostalCode1</PostalCode>
</Address>
</World>
要完成您的解决方案,您需要在“世界”中定义课程和成绩xs:key
“实体”,为每个实体定义类似于Student /* Address *,然后将CourseID和GradeID属性添加到需要它们的实体中,以及最后,如上所述,为Entity to Grade和Entity to Course定义 keyref 。