The SITE_VISIT_DURATION_SECONDS column stores the number of seconds between the first and last HTTP requests at a site during an HTTP session. A user may visit other sites and then return to the original site during this period. If the HTTP session ends by timing out, SITE_VISIT_DURATION_SECONDS does not include the time that passes after the last HTTP request.

The following diagram shows the period of time measured in the SITE_VISIT_DURATION_SECONDS column.