Lesson 21 / 23
Sharding
Scale horizontally by sharding collections across servers using a well-chosen shard key.
Splitting data by shard key
Sharding distributes a collection's documents across multiple servers (shards) based on a chosen shard key, instead of one server holding it all.
When you need it
Reach for sharding when data size or write/read throughput outgrows what a single replica set can handle.
Quick check: What problem does sharding primarily solve?
- Automatic failover when the primary goes down
- Validating document structure
- Formatting JSON output
- Scaling storage and throughput beyond a single server
Answer
Scaling storage and throughput beyond a single server — Sharding horizontally scales out data and load; failover is handled by replica sets instead.