Zeebe process database

Hi !

I’m developping an application with Zeebe at it’s core (I will deploy it in production so i can’t use Tasklist, Operate…). My business database is already setup.
According to my research, most BPMN engines integrate a process database (so we can query ongoing tasks, old processes…).

Looking at the documentation, Zeebe is event oriented and doesn’t provide this type of database.
Is doing it by hand with a worker the only solution ?
I see we can use exporters, can they be used to setup a procress DB or is it purely for logging purpose ?

Regards

Hi @Adrien_M

Correct. Zeebe does not use an RDMS. For querying ongoing tasks and old processes, you use an exporter, and then you need to reduce the state from the exported event stream.

Simple Monitor is an example of doing this.

Josh

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Hi @jwulf

Okey great I think I see where I’m going
Do you know why Simple Monitor uses hazelcast, it cannot connect to zebee directly (gRPC)?

Hi @Adrien_M,

to achieve the endless scalability, Zeebe is built on the Command-Query-Responsibility-Segregation pattern: CQRS. Zeebe consumes the commands and the exporter creates the data to answer the queries.

The state of all process instances is distributed over all cluster nodes and could not be queried here. The exporter writes the data into a single data sink, and the developers have choosen Hazelcast.

Hope this helps, Ingo

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Yep. gRPC is the Command channel.