Process History View can only query one event chronicle database at a time. When your event chronicle reaches the size or age limits configured, the data is either moved from the active db to a current (archive) db or is deleted, depending on your configuration. It's important to size your chronicles such that a reasonable amount of data (a year, perhaps), is available in the active db.
Now to query the current (not active) chronicles through PHV, use the Events:configure events menu to select a different chronicle, then perform your query again.
Youssef El-Bahtimy | Systems Integration Technologist PROCONEX | 103 Enterprise Drive | Royersford, PA 19468 USA Proconex Office: 610 495 2970 | Cell: 267 275 7513 Youssef.El-Bahtimy@ProconexDirect.com