Answer
A good sharding key ensures balanced data distribution, high cardinality, and avoids write hotspots, which affects scaling performance.
Quick Answer
The shard key determines how data is distributed across shards. A good shard key has high cardinality (many distinct values), even write distribution (avoid hotspots), and is included in most queries. Bad choices: monotonically increasing keys (like timestamps or ObjectId) cause all writes to go to one shard. Hash sharding distributes ObjectIds evenly across shards.
S
SugharaIQ Editorial Team
Verified Answer
This answer has been peer-reviewed by industry experts holding senior engineering roles to ensure technical accuracy and relevance for modern interview standards.
Want to bookmark, take notes, or join discussions?
Sign in to access all features and personalize your learning experience.
Source: SugharaIQ