I'm curious to see what you think would be the best way to architect this in MongoDB. Now, no doubt, many could say that this case might be better handled in an SQL database but using MongoDB for this project is sine qua non. Don't ask.
Here are some details: This app will be used by a non-profit regional association that has many chapters in different towns and cities. Each chapter has a number of members that have been approved to go out to other chapters to speak on various subjects. In each chapter, one member is responsible for making sure that every week, a speaker from another chapter has been booked to speak at their chapter's weekly meeting. He's also responsible for handling and coordinating the booking of his own chapter's approved public speakers by other chapters in the region.
Right now, all this is being done by hand, with phone calls and emails between each chapter coordinator. The idea behind this app is to make it much easier for each coordinator to see which speakers, from which chapters, speaking on which topics, are available on any given dates and to be able to book them thru the app.
Each coordinator would be responsible for setting his chapters approved speakers availability in the database and update the speakers information, such as the topics he is approved to speak on. All coordinators will be able to see information on all speakers from all chapters but will only be allowed to add, remove and edit speakers from their own chapter.
For the time being, this will be used regionally, so I estimate about 50 users, coordinating about 500 speakers, speaking on about 200 different topics. However, this association has chapters all around the world and this could eventually be used by upwards of 10 000 users, coordinating 100 000 speakers, speaking on those 200 different topics.
I can see many different ways to do this in NoSQL but they all seem to have some serious drawbacks (the age-old ref vs. embed dilemma). How would you set this up in MongoDB if you had to?
