I have hosted a test website (opencart) to do a R&D analysis on e-commerce tracking.
And I have installed piwik 2.12.1 and also enabled e-commerce tracking using an opencart plugin Piwik-OpenCart-Ecommerce-VQMod-2.0.
The dashboard and other reports works fine. But in the piwik_log_visit_action
table there is only data from a single date (Piwik enabled date) and there onwards there is no data getting saved in to the table.
But the e-commerce transactions are being listed in piwik dashboard.