PDO exception for Entity Reference Module
The reason is here:

[…] ON na.nid = node.nid WHERE (nid IN (:db_condition_placeholder_0)) […]


Can you see the nid after the WHERE keyword, it has no identifier and therefore PDO does not know how to handle it. You must prefix it with the correct table name (or assigned shortcut). Either na.nid or node.nid should do the trick.