Why shared database is a anti pattern?

Is shared database an anti-pattern?

Yes, shared database is an anti-pattern in micro services architecture. If one shared database can serve your system well then you don't need microservices. You should build a monolith instead. The main reason for using microservices is scale.

Why microservices should not share database?

Microservices with shared databases can't easily scale. Changes related to the database could impact multiple services. Besides, microservices won't be independent in terms of development and deployment as they connect to and operate on the same database.

What is shared database?

A Shared Database allows you to store your documents in your favorite relational (SQL) database rather than on the file system. This means that multiple users can concurrently use the same synchronized storage location without any problems.

Should different microservices share a database?

You are not likely to benefit from a Microservices architecture if all the services share the same database tables. This is because you are effectively tightly coupling the services. If a database table changes all the services will have to change.