In this article, we will discuss EventStoreDB. EventStoreDB is a database that allows the user to read and store events into fine-grained streams, as well as read all or a subset of events. It is an approach to building applications focused on storing state changes as they occur. First, we’ll look at the core topics like events, event sourcing, and event streams. So let’s start,
An event is an incident that is significant to the system. An event can be either a user action or a system state change, for example, a user double-clicking an icon on the taskbar to launch a new application or click to download something, or a file system crash due to memory exhaustion.
Events help us to understand what is happening in our systems and why it is happening, which allows us to take appropriate steps toward resolving the issues fastly and efficiently.
An event stream is nothing but a sequence of events, which are immutable and append-only. The EventStream constructor takes an event object as its argument and returns an EventStream instance that we can use to iterate through all the events in our database.
Event Sourcing is an application development approach focused on storing state changes as they occur.
It is an alternative method of data persistence. Event Sourcing stores each state mutation as a separate record known as an event, unlike state-oriented persistence, which only stores the latest version of an entity’s state.
It means that we capture every single change made in our system, no matter how small or big, and preserve it as part of the database at all times. It includes events like when something happened for example adding a user, who did it, and when it happened.
Benefits of Event Sourcing:
- One of the best solutions for an audit log is an event-based system that stores your data as a stream of volatile events over time.
- The ability to link business events back to their originating events enables full visibility and traceability of processes.
- EventStoreDb is a database server with the ability to store streams of events in sequence and allows you to efficiently query this data when needed. The core concept of the Event Store is an event stream, a series of events that appear in chronological order under a single name, identified by a GUID.
- It improves write performance since all types of events are simply appended to the data store. There are no updates and no deletes.
- Moving systems backward and forward in time is feasible since all state changes get preserved, which is incredibly helpful for debugging and “what if” research.
The Event Store is a database server with the ability to store streams of events in sequence. It allows you to efficiently query this data if you need to. The core concept of the Event Store is an event stream, a series of events that appear in chronological order under a single name, identified by a GUID. When an application subscribes to read from an EventStore instance, it receives the latest event using its default throttling policy (typically 1000 milliseconds). This means that when applications access your database, they should be able to do so without waiting for their turn to read data from it.
EventStoreDb is a database server with the capability to store streams of events in sequence, and it allows you to efficiently query this data if you need to. The core concept of Event Store is an event stream, a series of events that appear in chronological order under one name, identified by GUID.
Projection is an EventStoreDB subsystem that lets you append new events or link existing events to streams in a reactive manner. An event store database is both an event store database and a messaging system called a projection.
Projections require the event body to be in JSON.
Projections are based on time series data, so they are able to represent changes over time. The projection module can identify patterns in the incoming stream and then see how those patterns change over time
EventStoreDB vs Traditional Database
- EventStoreDB allows us to add or remove columns without changing the schema. This allows us to have our data in one place and access it from multiple applications at the same time.
- Storing events and messages in JSON format makes them easier for people to understand than using traditional database methods. It’s easier for users to query event data because it’s stored as JSON instead of SQL.
- EventStoreDB processes huge amounts of data with low overhead. This means that it will perform well even when working with large files or many transactions.
In conclusion, we get an Overview of EventstoreDB. Stay tuned. Read Official Documentation for more knowledge. Meanwhile, you can visit Knoldus Blogs to gain more information about different technologies.