DeepFrontend
Learning Paths
Practice
System Design & DS
Design Studio
Data Structures Curriculum
Real-World Case Studies
Careers
Job Board
Resume Builder
Blog
Sign in
Search
⌘K
Go Pro
Loading compiler resources...
Ask DeepFrontend AI
System Design Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
medium
System Design
Why does Notion store document pages as a flat dictionary of blocks (Record<BlockId, Block>) rather than a deeply nested JSON tree?
A
Because JSON cannot store strings longer than 100 characters
B
A flat normalized dictionary allows sub-millisecond lookups, simple block re-parenting, and prevents expensive recursive tree traversal queries
C
Because React cannot render nested components
D
Because IndexedDB only supports flat arrays
Check Answer