title: Aggregate/concatenate values from a column into a single row
body: <p>I have a couple thousand franchises, and about 3 or 4 service groups. The service groups are in a separate table, then i have third table joining them together. A franchise may be connected to 1 or many service groups. What I am trying to achieve is listing out the franchises, with a column labeled "Service Categories". It would then be a comma separated list of which services they provide. So right now, here's my output:</p>
  
  <pre><code>id  Service Groups     name                    email                address      City         State
  1   Cleaning Services  Franchise of LocationX  example@example.com  123 Fake st. Springfield  TheOneTheSimpsonsLiveIn
  2   Disaster Services  Franchise of LocationX  example@example.com  123 Fake st. Springfield  TheOneTheSimpsonsLiveIn
  </code></pre>
  
  <p>I would like to have it so it becomes this:</p>
  
  <pre><code>id  Service Groups                        name                    email                address      City         State
  1   Cleaning Services, Disaster Services  Franchise of LocationX  example@example.com  123 Fake st. Springfield  TheOneTheSimpsonsLiveIn
  </code></pre>
  
  <p>Any suggestions or references of methods/functions I can use to do this would be greately appreciated. Thanks!</p>