What is the difference between esper cep window, schema and context?

Question

I am new to esper cep. I need some clarification on the differences between esper window, context and schema. If possible provide examples

Answer 1

A window is something that retains a set of events. A context defines the life cycle of any analysis. So if that analysis includes a window then the context can be used to define when the window starts (when to start retaining events) and when it ends (when to throw the window away completely). Without a context the lifecycle starts when the EPL statement gets created and ends when the EPL statement gets destroyed. A schema provides event type information.

Answer 2

You should review Esper's comprehensive documentation on the topics you are interested in:

• window

• context

• schema

Esper recommends new users follow these steps to build up their event processing skills.

Note: These links point to Esper 5.2 documentation which will break once Esper stops hosting them (typically this will happen when 5.3 is released). If the links stop working just go to Esper's documentation page and look for similar sections in the current documentation.