title: Google App Engine: Should two tightly related entities be combined?
body: <p>In an application I'm developing I have two entities that are tightly related (EntityA, EntityB). EntityB is never accessed without EntityA, but EntityA is often accessed without Entity B. Also, EntityB can be very large, while EntityA is moderately sized.</p>
  
  <p>Is there any disadvantage to adding EntityB to EntityA (as a structured property/copying the field)? Thereby increasing the size of EntityA, and eliminating EntityB. Or should I just use a key property in EntityA to reference EntityB, and use an extra get whenever EntityB is needed?</p>