BAC-L0-FOUND-103
Databases, logs and state
A distributed ledger is first an ordered log whose state is a projection. This workshop plants that idea before it becomes a blockchain.
- Level
- L0 — Foundation
- Duration
- 3 h
- Track
- Foundation
- Maintainer
- Developer Curriculum Architect
Learning objectives
- 01Tell an event log apart from the state it produces
- 02Replay a log to rebuild a verifiable state
- 03Explain atomicity and durability on a concrete case
Guided lab
Build a small append-only ledger and rebuild balances by replaying the log.
Independent lab
Add periodic snapshots to the ledger and show that replay from a snapshot yields the same state.
Security angle
Tamper with a mid-log entry and observe what fails to detect it in the absence of cryptographic chaining.
Assessment
Working ledger plus a note explaining the log/state relationship.