NewSQL徹底入門 分散DBnのアーキテクチャからユースケースまで

NewSQL Technical Elements

• Storage Engine
  • LSM-Tree
• Sharding
  • Hash Sharding, Range Sharding
• Consensus Algorithm
  • Raft, Paxos, ...
• Distributed Transaction
  • Transaction Isolation Level
    • serializable
    • snapshot isolation
    • repeatble read
    • read committed
    • read uncimmitted
  • Pessimistic Concurrency Control / Optimistic Concurrency Control
  • Clock Skew
    • Spanner: [earliest, latest], Atomic Clock, GPS
  • Linearlizability
  • Timestamp Oracle TiDB
    • Under geo partitioning, effect network connection/latency
  • Hyblid Logical Clock

In fifth section, regarding write skew. This issue originates from a buisiness logic example described in "Designing Data-Intensive Appliation". It occurs between two transactions whose target redcords are different. While I agree that changing the transaction isolation level to serializable is one solution, in this case I believe it is better to redesign the table schema or introduce an explicit locking mechanism to coordinate the two transaction rather than changing the isolation level.

Vendor Production Architechture

• TiDB, CockroachDB, YugabyteDB