Hello Everyone,
I am a fullstack dev and wanted to build a social media platform to explore the possibilities with different databases 
But I am really struggling to decide what should be the best database or databases to implement all these features like:
- Community detection
- Trend detection (last year, month, week, day, 7hours, 15mn)
— trending categories
— trending posts - Counters
— total users
— total friends
— total posts and total per user
— total comments etc… - Search engine
— search users / posts / categories (with trending ones at the top)
I understand that Graphdb are perfect for community detection but not for trend detections where time series db seems more adequate.
For the search feature I am not sure what to use to be able to search any keywords like name, lastname, posts, categories or even the content of a post.
The idea is to design it and test for 10 million users posting 10 posts a day each (at least 
)
Will you use only 1 database to achieve all that or will you use different databases and connect them together to get the best from all ?
Could you guys tell me what you will use to cover each of these feature please ???
Thank you for the time you’ve spend reading and helping me out 
