title: use of bridge table with multi column joins in icCube
body: <p>I have a question on best practice for a bridge table design:</p>
  
  <p>I have a Fact table that has the following 3 columns where the primary keys are in bold:</p>
  
  <p><strong>Generator</strong><br/>
  <strong>FuelType</strong><br/>
  FuelCost</p>
  
  <p>I then have a Generator dimension with the following columns:</p>
  
  <p><strong>Generator</strong><br/>
  PrimaryFuelType<br/>
  SecondaryFuelType</p>
  
  <p>I would like to be able to view my results by the combination of {Generator,PrimaryFuelType} and {Generator,SecondaryFuelType}</p>
  
  <p>I was planning on creating 2 measure groups based on the Fact table and use my Generator dimension as a bridge in both. Basically have {Generator,FuelType} as the Join Columns (fact table) and {Generator,PrimaryFuelType} as Join columns (Bridge table). For the 2nd measure group it would then be {Generator,SecondaryFuelType} as Join columns (Bridge table).</p>
  
  <p>Is that the best way to approach it? Would a potential restructuring of the data format in the dimension table make this more efficient.</p>
  
  <p>thanks,
  John</p>