Glossary

Sharding

Splitting data across many databases by a shard key so it scales past one node.

1 min read·4 sections
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Definition

Splitting data across many databases by a shard key so it scales past one node.

How it works

A bad key creates a hot shard; cross-shard joins/transactions get hard.

Common questions

What is Sharding?

Splitting data across many databases by a shard key so it scales past one node.

How does Sharding work?

A bad key creates a hot shard; cross-shard joins/transactions get hard.

What is Sharding used for in system design?

A bad key creates a hot shard; cross-shard joins/transactions get hard.

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