MongoDB: How to represent a schema diagram in a thesis?

Question

I am currently writing a thesis and need to display the schema of my MongoDB in a diagram. I have found no resources about diagrams for document-based databases.

There are Entity Relationship Diagrams (ERD) for relational databases. What options do I have for MongoDB? I've noticed that a lot of blogs just display the raw JSON as their "diagram" but this isn't feasible in my thesis.

Here is a sample of one of my JSON structures:

//MultiChoiceQuestion {     "title": "How are you?",     "valid_answers" : [         {             "_id" : ObjectID(xxxx),             "title": "Great",             "isCorrect": true,         },         {             "_id" : ObjectID(yyyy),             "title": "OK",             "isCorrect": false,         },         {             "_id" : ObjectID(zzzz),             "title": "Bad",             "isCorrect": false,         }     ],     "user_responses" : [         {             "user": ObjectID(aaaa),             "answer": ObjectID(xxxx)         },         {             "user": ObjectID(bbbb),             "answer": ObjectID(xxxx)         },         {             "user": ObjectID(cccc),             "answer": ObjectID(yyyy)         }     ] }  //User {     "_id": ObjectID(aaaa),     "name": "Person A" } //User {     "_id": ObjectID(bbbb),     "name": "Person B" } //User {     "_id": ObjectID(cccc),     "name": "Person C" } 

Could this be a possible diagram:

Answer 1

We found class diagrams to actually be one of the best ways to represent a mongo schema design.

It can capture most of the items that a document will have such as arrays, embedded objects and even references.

General guidelines we use to relate onto concepts to uml

Embed = Composition aggregation

Reference = Association class

If you're unfamiliar with the uml terminology then this is a decent intro.

UML intro from IBM site