Transactional Outbox

Definitions

1. A pattern where events destined for a message broker are first written to an 'outbox' table within the same database transaction as the business data change, then a separate process (polling or CDC) reliably publishes them — guaranteeing that the event is sent if and only if the transaction commits.

   In plain English: A technique to make sure that when you save data to a database, the corresponding notification always gets sent too — never one without the other.

   Example: "Without the transactional outbox, a crash between the DB commit and the Kafka publish meant the order was created but the warehouse never got notified."

Related Terms

• CAP Theorem
• Kafka Stream
• Message Broker
• Read Concern
• Subscriber
• TLA+
• Zeromq
• RabbitMQ