diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index d26db7d4cf..e232516b0c 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -24,12 +24,12 @@ module ActiveRecord
     end
 
     def build_from_hash(attributes)
-      attributes = convert_dot_notation_to_hash(attributes.stringify_keys)
+      attributes = convert_dot_notation_to_hash(attributes)
       expand_from_hash(attributes)
     end
 
     def create_binds(attributes)
-      attributes = convert_dot_notation_to_hash(attributes.stringify_keys)
+      attributes = convert_dot_notation_to_hash(attributes)
       create_binds_for_hash(attributes)
     end
 
diff --git a/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb
index 159889d3b8..e81be63cd3 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/association_query_handler.rb
@@ -10,10 +10,10 @@ module ActiveRecord
 
         table = value.associated_table
         if value.base_class
-          queries[table.association_foreign_type] = value.base_class.name
+          queries[table.association_foreign_type.to_s] = value.base_class.name
         end
 
-        queries[table.association_foreign_key] = value.ids
+        queries[table.association_foreign_key.to_s] = value.ids
         predicate_builder.build_from_hash(queries)
       end
 
diff --git a/activerecord/lib/active_record/relation/where_clause_factory.rb b/activerecord/lib/active_record/relation/where_clause_factory.rb
index 0430922be3..23eaab4699 100644
--- a/activerecord/lib/active_record/relation/where_clause_factory.rb
+++ b/activerecord/lib/active_record/relation/where_clause_factory.rb
@@ -15,6 +15,7 @@ module ActiveRecord
         when Hash
           attributes = predicate_builder.resolve_column_aliases(opts)
           attributes = klass.send(:expand_hash_conditions_for_aggregates, attributes)
+          attributes.stringify_keys!
 
           attributes, binds = predicate_builder.create_binds(attributes)