Event Sourcing - A Comprehensive Guide

Microservices & Architecture

Event Sourcing is a technique where the state of your system is stored as a sequence of events. This approach offers significant advantages for building resilient and scalable microservices architectures.

It’s essentially about capturing every change that happens to an object or system as a discrete event, providing a complete audit trail and enabling powerful querying capabilities.

Full Audit History

Event Sourcing provides the ability of ‘time travel’, meaning you can reconstruct the state of your system at any point in time by replaying the events that occurred up to that moment.

This capability is invaluable for debugging, analyzing historical trends, and ensuring compliance with regulatory requirements. It also simplifies auditing processes significantly.

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Efficient Querying by Aggregate ID

By focusing on the aggregate ID – a unique identifier for each entity – you can efficiently replay events to reconstruct the current state of that aggregate.

This approach allows you to ‘replay’ the entire history of an object or system, effectively creating a snapshot of its state at any given point in time without relying on complex database queries.

Frequently asked questions

What are Materialized Views?

Materialized views are pre-computed representations of data, designed to improve query performance. They store the results of a complex query as a separate table.

Are Search Indexes used for searching?

Search indexes are specifically designed to accelerate the retrieval of information within large datasets by creating an indexable structure for efficient searching.

What are Reporting Models?

Reporting models are structured representations of data tailored for generating reports and analyses, facilitating the creation of insightful visualizations and summaries.

Do we store events immutably?

Yes, it’s crucial to store events immutably. This means that once an event is written, it cannot be modified or deleted – ensuring the integrity of your audit trail.

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Everything above runs in your browser — open Hash Function Avalanche Visualizer and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.

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