1、最近一直在研究Mondrian如何构建Schema4.0的雪花模型，和星星模型，刚开始研究了大半天都在看Schema3.0的，太坑了。这东西比较是国外研究的技术，许多api文档都英文的，国内很少资料。只能硬着头皮干。哈哈。废话不多说，直接上代码。
表关系，如下：
注意：其实雪花模型已经包含星星模型，不懂得可以查查资料
Schema4.0雪花模型如下：
<Schema metamodelVersion='4.0' name='test'>
<Cube name='HR'>
<Dimensions>
<Dimension name='Employee' key='Employee Id'>
<Attributes>
<Attribute name='Manager Id' table='employee' keyColumn='supervisor_id'/>
<Attribute name='Employee Id' table='employee' keyColumn='employee_id' nameColumn='full_name' orderByColumn='employee_id'/>
<Attribute name='Store Id' table='employee' keyColumn='store_id'/>
<Attribute name='Store Type' table='store' keyColumn='store_type' hierarchyAllMemberName='All Store Types'/>
<Attribute name='Pay Type' table='position' keyColumn='pay_type' hierarchyAllMemberName='All Pay Types'/>
<Attribute name='Management Role' table='position' keyColumn='management_role'/>
<Attribute name='Position Title' table='position'>
<Key>
<Column name='management_role'/>
<Column name='position_title'/>
</Key>
<Name>
<Column name='position_title'/>
</Name>
<OrderBy>
<Column name='position_id'/>
</OrderBy>
</Attribute>
<Attribute name='Marital Status' table='employee' keyColumn='marital_status'/>
<Attribute name='Gender' table='employee' keyColumn='gender'/>
<Attribute name='Salary' table='employee' keyColumn='salary'/>
<Attribute name='Education Level' table='employee' keyColumn='education_level'/>
</Attributes>
<Hierarchies>
<Hierarchy name='Employees' allMemberName='All Employees'>
<Level attribute='Employee Id' parentAttribute='Manager Id' nullParentValue='0'>
<Closure table='employee_closure' parentColumn='supervisor_id' childColumn='employee_id'/>
</Level>
</Hierarchy>
<Hierarchy name='Position' allMemberName='All Position'>
<Level attribute='Management Role'/>
<Level attribute='Position Title'/>
</Hierarchy>
</Hierarchies>
</Dimension>
<Dimension name="Actual VS Budget" hanger="true">
<Attributes>
<Attribute name="Type"/>
</Attributes>
</Dimension>
<Dimension name='Department' table='department' key='Department Description'>
<Attributes>
<Attribute name='Department Description' keyColumn='department_id'/>
</Attributes>
<Hierarchies>
<Hierarchy name='Department2'>
<Level attribute='Department Description'/>
</Hierarchy>
</Hierarchies>
</Dimension>
<!-- Use private "Time" dimension because key is different than public
"Time" dimension. -->
<Dimension name='Time' table='time_by_day' type='TIME' key='Time Id'>
<Attributes>
<Attribute name='Year' keyColumn='the_year' levelType='TimeYears' hasHierarchy='false'/>
<Attribute name='Quarter' levelType='TimeQuarters' hasHierarchy='false'>
<Key>
<Column name='the_year'/>
<Column name='quarter'/>
</Key>
<Name>
<Column name='quarter'/>
</Name>
</Attribute>
<!-- Use the_month as source for the name, so members look like
[Time].[1997].[Q1].[Jan] rather than [Time].[1997].[Q1].[1]. -->
<Attribute name='Month' hasHierarchy='false'>
<Key>
<Column name='the_year'/>
<Column name='month_of_year'/>
</Key>
<Name>
<Column name='the_month'/>
</Name>
</Attribute>
<Attribute name='Date' keyColumn='the_date' hasHierarchy='false'/>
<Attribute name='Time Id' keyColumn='time_id' hasHierarchy='false'/>
</Attributes>
<Hierarchies>
<Hierarchy name='Time' hasAll='false'>
<Level attribute='Year'/>
<Level attribute='Quarter'/>
<Level attribute='Month'/>
</Hierarchy>
</Hierarchies>
</Dimension>
<Dimension source='Store'/>
</Dimensions>
<MeasureGroups>
<MeasureGroup name='HR' table='salary'>
<Measures>
<Measure name='Org Salary' column='salary_paid' aggregator='sum'
formatString='Currency'/>
<Measure name='Count' column='employee_id' aggregator='count'
formatString='#,#'/>
<Measure name='Number of Employees' column='employee_id'
aggregator='distinct-count' formatString='#,#'/>
</Measures>
<DimensionLinks>
<ForeignKeyLink dimension='Time' foreignKeyColumn='pay_date' attribute='Date'/>
<ForeignKeyLink dimension='Department' foreignKeyColumn='department_id'/>
<ForeignKeyLink dimension='Employee' foreignKeyColumn='employee_id'/>
<ReferenceLink dimension='Store' viaDimension='Employee' viaAttribute='Store Id'/>
</DimensionLinks>
</MeasureGroup>
</MeasureGroups>
<CalculatedMembers>
<CalculatedMember name='Employee Salary' dimension='Measures'
formatString='Currency'
formula='([Employees].currentmember.datamember, [Measures].[Org Salary])'/>
<CalculatedMember name='Avg Salary' dimension='Measures'
formatString='Currency'
formula='[Measures].[Org Salary]/[Measures].[Number of Employees]'/>
<CalculatedMember name="Test" hierarchy="[Store].[Stores]" formula="[Store].[Stores].[All Stores]"/>
</CalculatedMembers>
<CalculatedMember hierarchy="[Actual VS Budget].[Type]" name="Actual">
<Formula>
[Store].[Stores].[All Stores]
</Formula>
</CalculatedMember>
</Cube>
<PhysicalSchema>
<Table name='department'>
<Key>
<Column name='department_id'/>
</Key>
</Table>
<Table name='employee'>
<Key>
<Column name='employee_id'/>
</Key>
</Table>
<Table name='position'>
<Key>
<Column name='position_id'/>
</Key>
</Table>
<Link source='position' target='employee'>
<ForeignKey>
<Column name='position_id'/>
</ForeignKey>
</Link>
<Table name='promotion'>
<Key>
<Column name='promotion_id'/>
</Key>
</Table>
<Table name='store'>
<Key>
<Column name='store_id'/>
</Key>
</Table>
<Link source='store' target='employee'>
<ForeignKey>
<Column name='store_id'/>
</ForeignKey>
</Link>
<Table name='product' keyColumn='product_id'/>
<Table name='product_class' keyColumn='product_class_id'/>
<Link target='product' source='product_class'>
<ForeignKey>
<Column name='product_class_id'/>
</ForeignKey>
</Link>
<Table name='time_by_day'>
<Key>
<Column name='time_id'/>
</Key>
</Table>
<Table name='warehouse'>
<Key>
<Column name='warehouse_id'/>
</Key>
</Table>
</PhysicalSchema>
</Schema>
重点维度Employee中是没有table属性，Attribute里面table的不同表名称。
employee作为实时表，store和region划分为维表。
employee和store关系为星星模型，employee->strore->region关系为雪花模型。
注意：在PhysicalSchema里面，Link表之间的关系得描述清楚哦。
<Link source='store' target='employee'>
<ForeignKey>
<Column name='store_id'/>
</ForeignKey>
</Link>
source 来源表（主表）target 目标表（子表）
自己理解的不完全正确，可以参考。维表的度量其实在数据模型中就不体现，维表的维度作为切面层级对实时表的度量进行分析。