[I work for MongoDB] For your use case, I would consider just holding all of the data in MongoDB. With an appropriate data model, you'd be able to quickly retrieve the information you need for the initial page display as well as article details.

This isn't to say that there aren't use cases that might be better served by either database or a combination, but for your particular use, you may not be gaining enough to offset the added complexity of using two different databases.

Obv. I'm biased, but I would recommend using MongoDB :)

Here's a reference for some design patterns to consider: https://www.mongodb.com/company/blog/building-with-patterns-...

there are foreign data wrappers for MongoDB. Check github

Foreign data wrappers