0 - 2 of 2 tags for X views

I was wondering if there was a query to enumerate all the databases/tables to which I have access, given I have logged on via LDAP.  The results of querying the X Views, such as dbc.DatabasesVX and dbc.TablesVX do not show all of the databases and tables I have access to, so it would seem a more complex solution would be required.

What is the difference between simple system view like dbc.tables, X views and V views and which one is better - performace wise?
Does every system view like dbc.tables will always have a corresponding X and V view? I failed to find any X or V view for for dbc.ErrorMsgs?