diff -r ad66d7b3fd48 -r 39b7a91a3f4c server/sources/rql2sql.py
--- a/server/sources/rql2sql.py	Mon Jul 01 16:13:17 2013 +0200
+++ b/server/sources/rql2sql.py	Thu Jan 23 12:32:16 2014 +0100
@@ -58,8 +58,8 @@
 from rql import BadRQLQuery, CoercionError
 from rql.utils import common_parent
 from rql.stmts import Union, Select
-from rql.nodes import (SortTerm, VariableRef, Constant, Function, Variable, Or,
-                       Not, Comparison, ColumnAlias, Relation, SubQuery, Exists)
+from rql.nodes import (VariableRef, Constant, Function, Variable, Or,
+                       Not, Comparison, ColumnAlias, Relation, SubQuery)
 
 from cubicweb import QueryError
 from cubicweb.rqlrewrite import cleanup_solutions