Marketplace - Public Discussion Forum

Functional Requirements

• User should be able to post questions/news
• What does it contain? Images, text, tags?
• Who can create and view posts?
• User should be able to comment on existing posts
• Comment on another comment?
• User should be able to upvote/downvote posts/comments
• User should be able to see the feed with the most popular posts
• The most popular post is the most voted?

Non-Functional Requirements

• Scalability
• Total Users
  • 200M customers
• Daily access
  • 100M customers/day
• Daily created posts
  • 10M posts/day
• Daily comments
  • 100M comments/day
• Daily upvote/downvote
  • 200M votes/day
• Geographic distribution
  • Global
• Performance
• Response time requirements (all APIs)
• Availability
• Availability + Partition Tolerance (AP over CP)

System Constraints

• Number of engineers and teams and will be working on this project
• 20 engineers, 3 teams

SQL

SELECT
Post\_post\_id,
SUM(votes.vote\_id) num\_of\_votes
FROM
posts
JOIN
votes
ON votes.parent\_id \= posts.post\_id
GROUP BY
post.post\_id
ORDER BY
num\_of\_votes DESC
LIMIT 10