Table references log_link_visit_action

Hi Everybody,

I am trying to understand the database structure of piwik (v 1.7.1). There are 2 things I cannot figure out:

1) I understand that log_link_visit_action is logging each action / pageview. idvisit is referencing a visit in log_visit. But how exactly is the action referenced. The data model documentation says with the field idaction, but in fact this field doesn’t exist. There are the fields:
idaction_url,
idaction_url_ref,
idaction_name,
idaction_name_ref

2) What is the purpose of idsite?

Hope anybody can help.

C