1 files changed, 7 insertions, 12 deletions
diff --git a/sqlglot/optimizer/pushdown_predicates.py b/sqlglot/optimizer/pushdown_predicates.py
index 9c8d71d..583d059 100644
--- a/sqlglot/optimizer/pushdown_predicates.py
+++ b/sqlglot/optimizer/pushdown_predicates.py
@@ -1,8 +1,6 @@
-from collections import defaultdict
-
 from sqlglot import exp
 from sqlglot.optimizer.normalize import normalized
-from sqlglot.optimizer.scope import traverse_scope
+from sqlglot.optimizer.scope import build_scope
 from sqlglot.optimizer.simplify import simplify
 
 
@@ -22,15 +20,10 @@ def pushdown_predicates(expression):
     Returns:
         sqlglot.Expression: optimized expression
     """
-    scope_ref_count = defaultdict(lambda: 0)
-    scopes = traverse_scope(expression)
-    scopes.reverse()
-
-    for scope in scopes:
-        for _, source in scope.selected_sources.values():
-            scope_ref_count[id(source)] += 1
+    root = build_scope(expression)
+    scope_ref_count = root.ref_count()
 
-    for scope in scopes:
+    for scope in reversed(list(root.traverse())):
         select = scope.expression
         where = select.args.get("where")
         if where:
@@ -152,9 +145,11 @@ def nodes_for_predicate(predicate, sources, scope_ref_count):
                 return {}
             nodes[table] = node
         elif isinstance(node, exp.Select) and len(tables) == 1:
+            # We can't push down window expressions
+            has_window_expression = any(select for select in node.selects if select.find(exp.Window))
             # we can't push down predicates to select statements if they are referenced in
             # multiple places.
-            if not node.args.get("group") and scope_ref_count[id(source)] < 2:
+            if not node.args.get("group") and scope_ref_count[id(source)] < 2 and not has_window_expression:
                 nodes[table] = node
     return nodes