Transaction_Log_Tailing.md

Transaction Log Tailing

• Motivation
• Solution
  • Concepts
  • Implementation
• Pros & Cons
  • Pros
  • Cons
• Consideration
• When To Use
• References

Motivation

• How to update the database and publish a message (event) atomically (either all success, or all fail).
• Cannot use distributed transaction pattens to solve this problem.
  • Many modern message brokers don’t support distributed transactions.

Solution

Concepts

• Publish messages by tailing the database’s transaction log.
• A transaction log miner reads the transaction log and publish each change as a message to the message broker.

Implementation

• Requires database specific solutions.
• It can be difficult to reverse engineer the high‑level business events from the low‑level updates recorded in the transaction log.

Pros & Cons

Pros

• The atomicity of updating the database and publishing a message (event) is guaranteed.

Cons

• Requires database specific solutions.

Consideration

Topic	Consideration	Possible Solution Options

When To Use

References

• Book: Chris R.(2018). Chapter 3. Interprocess communication in a microservice architecture, Microservices Patterns (pp. 65-109). Manning Publications
• Book: Kasun I., Prabath S.(2018). Chapter 5: Data Management, Microservices for the Enterprise (pp. 125-150). Apress
• Web Article: Pattern: Transaction log tailing | https://microservices.io/patterns/data/transaction-log-tailing.html
• Web Article: Event-Driven Data Management for Microservices | https://www.nginx.com/blog/event-driven-data-management-microservices/