What is ActiveMQ used for - can we apply messaging concept using a Database?

Question

I looked it up and it used to send messages between 2 systems.
But why? Why wouldn\'t you just use a Database?
There must be some feature that ActiveM

Answer 1

ActiveMQ has great scheduler support, which means you can schedule sending your message to be delivered at a particular time.

We have used this feature to send medication reminders to patients uploading their medication details in a health care scenario.