title: Objects in core data share the same information and don't fully delete
body: <p>I have an app that uses core data to store two UITables of information. When the a collection row is tapped it shows a table that has pictures. The option to add a picture or collection is indicated with the +. When ever a new picture object is inserted  <code>[collection addPhotoObject:photo];</code>  and you navigate to another collection it has the same row there. Even when all the collections are deleted and a new one is added, it has the same info as the old one(s). How can this be prevented?</p>
  
  <p>Has this been encountered before? Any suggestions?</p>
  
  <p>Thanks in advance!</p>