Client events and threat events make up most of the event data in your database. Queries help you track how many events are stored in your database.
Event summary queries help you manage any performance problems that these events might cause for your ePO - On-prem server and database.
Client events from your agents relate their task status to ePO - On-prem. Items like update complete, update failed, deployment completed, or encryption started are considered client events. Threat events include a virus was found, a DLP event was triggered, or an intrusion was detected. Depending on which products you have installed and which events you are collecting, there might be thousands or even millions of these events in your database.