D8LooP - Practise Data Engineering

Preparing your workspaceloading the brief, studio & canvas…

buyersellerlistingorder

SCENARIO

You've joined SocialHub. A user can react to a post, change their reaction, or remove it — and the client emits an event for each. Because of retries, events sometimes arrive out of order: the removal occasionally lands before the add it removes. Product wants daily engagement. Support separately needs *"what is this user's reaction on this post right now?"*

your model must answer

01Reactions on a post yesterday, net of removals?
02Distinct users who reacted to a post last week?
03Daily reaction counts broken out by type for one post?

out of scopeNotifications · feed ranking · moderation · threads · the picker

This exercise’s brief could not be loaded.The guided questions and their model answers come from the review service. It looks like it is not reachable — start it with pnpm dev:api and reload.The canvas below still works, so you can model now and run the review once the service is up.

Build starts here

The brief becomes the left drawer. The canvas stays the build surface.Study is done above. Build the tables here, hit review to validate, then use follow-ups to defend the model.

Practice studio

Ctrl/Cmd + C copyCtrl/Cmd + V pasteCtrl/Cmd + Z undoDelete remove

Start with the data model, then layer system context

Use entities and relationships for the real ERD. Add notes, containers, or curated cloud shapes only when they sharpen the story you are architecting.

68%

You built the model in the Studio. Now defend it.Engagement from a messy event log

Design review

The reviewer reads your model.

Preparing your workspaceloading the brief, studio & canvas…

buyersellerlistingorder

SCENARIO

your model must answer

01Reactions on a post yesterday, net of removals?
02Distinct users who reacted to a post last week?
03Daily reaction counts broken out by type for one post?

out of scopeNotifications · feed ranking · moderation · threads · the picker

Build starts here

The brief becomes the left drawer. The canvas stays the build surface.Study is done above. Build the tables here, hit review to validate, then use follow-ups to defend the model.

Practice studio

Ctrl/Cmd + C copyCtrl/Cmd + V pasteCtrl/Cmd + Z undoDelete remove

Start with the data model, then layer system context

Use entities and relationships for the real ERD. Add notes, containers, or curated cloud shapes only when they sharpen the story you are architecting.

68%

You built the model in the Studio. Now defend it.Engagement from a messy event log

Design review