每个应用程序都有一个数据库的原因

Question

We are defining an architecture for a coupe of connected applications, and we are discussing why should we have or not have a shared database many applications can access. I would like to ask what are the benefits/disadvantages of having a shared database vs having a database per application?

Answer 1

As per the definition of mircoservices each service should be independent. You may save ressources by using a single database, but it destroys the benefits of dynamic scaling or availability. By using a single database you create a single-point-of-failure which is an anti-pattern in the microservice world.

Another reason for using seperate databases might be for optimization. One service might require a relational database, but another one stores for example analytical data where a time-series database is a better fit.