See the following article:
https://www.ibm.com/support/pages/event-processing-pipelineThe events get stored on the EP and/or on the DataNode that is attached to the EP.
They get stored there up to the duration of the retention policy for events which is set in Admin > Event Retention in the UI.
They are stored in compressed archives.
I do not think you would want events to be stored in text/csv format (they are stored as compressed archives) as you would quickly run out of space and searches would most likely become inefficient.
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Adam Mcdonald
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