--- a/server/sources/rql2sql.py	Tue Sep 15 19:04:09 2009 +0200
+++ b/server/sources/rql2sql.py	Wed Sep 16 14:16:19 2009 +0200
@@ -336,6 +336,7 @@
         self._varmap = varmap
         self._query_attrs = {}
         self._state = None
+        self._not_scope_offset = 0
         try:
             # union query for each rqlst / solution
             sql = self.union_sql(union)
@@ -553,7 +554,11 @@
 
     def visit_not(self, node):
         self._state.push_scope()
+        if isinstance(node.children[0], Relation):
+            self._not_scope_offset += 1
         csql = node.children[0].accept(self)
+        if isinstance(node.children[0], Relation):
+            self._not_scope_offset -= 1
         sqls, tables = self._state.pop_scope()
         if node in self._state.done or not csql:
             # already processed or no sql generated by children
@@ -1080,12 +1085,16 @@
         # a EXISTS node
         if var.sqlscope is var.stmt:
             scope = 0
+        # don't consider not_scope_offset if the variable is only used in one
+        # relation
+        elif len(var.stinfo['relations']) > 1:
+            scope = -1 - self._not_scope_offset
         else:
             scope = -1
         try:
             sql = self._varmap[var.name]
             table = sql.split('.', 1)[0]
-            if scope == -1:
+            if scope < 0:
                 scope = self._varmap_table_scope(var.stmt, table)
             self.add_table(table, scope=scope)
         except KeyError:
@@ -1146,8 +1155,8 @@
             key = table
         if key in self._state.tables:
             return
-        if scope == -1:
-            scope = len(self._state.actual_tables) - 1
+        if scope < 0:
+            scope = len(self._state.actual_tables) + scope
         self._state.tables[key] = (scope, table)
         self._state.actual_tables[scope].append(table)