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HLDsystem_design~10 mins

Video recommendation system in HLD - Interactive Code Practice

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Practice - 5 Tasks
Answer the questions below
1fill in blank
easy

Complete the code to identify the main component responsible for storing user watch history.

HLD
The component that stores user watch history is called the [1].
Drag options to blanks, or click blank then click option'
AWatch History Store
BUser Profile Database
CRecommendation Engine
DContent Delivery Network
Attempts:
3 left
💡 Hint
Common Mistakes
Confusing the recommendation engine with the storage component.
Choosing content delivery network which only serves videos.
2fill in blank
medium

Complete the code to specify the type of database best suited for storing video metadata.

HLD
For storing video metadata like title, description, and tags, a [1] database is preferred.
Drag options to blanks, or click blank then click option'
AGraph
BRelational
CTime-series
DKey-Value
Attempts:
3 left
💡 Hint
Common Mistakes
Choosing key-value stores which are better for caching.
Choosing graph databases which are better for social connections.
3fill in blank
hard

Fix the error in the description of the recommendation algorithm type.

HLD
The system uses a [1] filtering algorithm that recommends videos based on user similarity.
Drag options to blanks, or click blank then click option'
ACollaborative
BContent-based
CHybrid
DRule-based
Attempts:
3 left
💡 Hint
Common Mistakes
Confusing content-based filtering which uses item features.
Choosing rule-based which is manual and static.
4fill in blank
hard

Fill both blanks to complete the request flow for serving a video recommendation.

HLD
User request -> [1] -> [2] -> Response with recommended videos
Drag options to blanks, or click blank then click option'
ARecommendation Service
BUser Profile Store
CVideo Metadata Store
DContent Delivery Network
Attempts:
3 left
💡 Hint
Common Mistakes
Mixing up user profile store with video metadata store.
Placing content delivery network before recommendation service.
5fill in blank
hard

Fill all three blanks to complete the capacity estimation formula for the recommendation system.

HLD
Total requests per second = [1] * [2] * [3]
Drag options to blanks, or click blank then click option'
ANumber of active users
BAverage requests per user per second
CReplication factor
DCache hit ratio
Attempts:
3 left
💡 Hint
Common Mistakes
Including cache hit ratio which reduces load, not increases it.
Confusing replication factor with cache hit ratio.