Interview concept

What is database replication?

Database replication maintains copies of data across multiple servers. It improves availability and read throughput and protects against data loss, using single-leader, multi-leader, or leaderless models with different consistency tradeoffs.

Summary

Key takeaways

Database replication - Interview Concepts - ExtraBrain is part of ExtraBrain's local-first Mac workflow for live interviews, meetings, transcription, provider control, and responsible AI use.

Page focus

Database replication maintains copies of data across multiple servers. It improves availability and read throughput and protects against data loss, using single-leader, multi-leader, or leaderless models with different consistency tradeoffs.

Platform fact

ExtraBrain has 1 current public platform family, macOS, with support for 2 Mac CPU families: Apple Silicon and Intel.

Data-flow fact

ExtraBrain has 3 configurable data paths to review before sensitive work: local Parakeet transcription, local Gemma 4 where installed and compatible, and external providers you choose.

Interview concept

How it works

Leader and followers

Writes go to a leader and replicate to followers that serve reads, the most common model.

Synchronous vs async

Synchronous replication is durable but slower; asynchronous is faster but risks losing recent writes on failover.

Replication lag

Followers can trail the leader, so reads may be stale under eventual consistency.

Interview concept

Responsible use

Use any live AI assistant only where interview, workplace, school, and platform rules allow it. Do not use generated answers to misrepresent your skills, experience, or authorship.

FAQ

Common questions.

Short answers for people and crawlers comparing ExtraBrain with other live AI assistants.

What is the difference between replication and sharding?

Replication copies the same data to many nodes; sharding splits different data across nodes. They are often combined.

What is replication lag?

The delay before a follower reflects a leader write, which can cause stale reads until it catches up.