Log data

The HTTP tracking API (i.e. the Piwik\Tracker component) receives raw analytics data, which we call log data.

There are five types of log data:

visits
action types
plugin specific actions
conversions
ecommerce items

Log data is aggregated by the Archiving process into archive data.

Log data is never used directly for Matomo (formerly Piwik) reports, archive data is used instead. The only exception is the Live plugin which uses log data to generate real-time reports.

Persistence

Log data is represented in PHP as Piwik\Tracker\Visit objects, and is stored into the following tables:

log_visit contains one entry per visit (returning visitor)
log_action contains all the type of actions possible on the website (e.g. unique URLs, page titles, download URLs…)
log_link_visit_action contains one entry per action of a visitor (page view, …)
log_conversion contains conversions (actions that match goals) that happen during a visit
log_conversion_item contains e-commerce conversion items

The content of those tables (and their related PHP entities) is explained in more details in the Database schema guide.