Merge pull request #47940 from fatkodima/fix-alias-where-missing

Remove table alias added when using `where.missing` or `where.associated`

activerecord/lib/active_record/relation/query_methods.rb

@@ -76,7 +76,11 @@ def associated(*associations)
         associations.each do |association|
           reflection = scope_association_reflection(association)
           @scope.joins!(association)
-          self.not(association => { reflection.association_primary_key => nil })
+          if @scope.table_name == reflection.table_name
+            self.not(association => { reflection.association_primary_key => nil })
+          else
+            self.not(reflection.table_name => { reflection.association_primary_key => nil })
+          end
         end
 
         @scope
@@ -104,7 +108,11 @@ def missing(*associations)
         associations.each do |association|
           reflection = scope_association_reflection(association)
           @scope.left_outer_joins!(association)
-          @scope.where!(association => { reflection.association_primary_key => nil })
+          if @scope.table_name == reflection.table_name
+            @scope.where!(association => { reflection.association_primary_key => nil })
+          else
+            @scope.where!(reflection.table_name => { reflection.association_primary_key => nil })
+          end
         end
 
         @scope

activerecord/test/cases/relation/where_chain_test.rb

@@ -43,6 +43,10 @@ def test_associated_with_invalid_association_name
       assert_match(/An association named `:cars` does not exist on the model `Post`\./, e.message)
     end
 
+    def test_associated_merged_with_scope_on_association
+      assert_equal Author.find(1).posts.count, Post.where.associated(:author).merge(Author.where(id: 1)).count
+    end
+
     def test_missing_with_association
       assert posts(:authorless).author.blank?
       assert_equal [posts(:authorless)], Post.where.missing(:author).to_a
@@ -68,6 +72,12 @@ def test_missing_with_multiple_association
       assert_equal [posts(:authorless)], Post.where.missing(:author, :comments).to_a
     end
 
+    def test_missing_merged_with_scope_on_association
+      # This query does not make much logical sense, but it is testing
+      # that the generated SQL query is valid.
+      assert_equal Author.find(1).posts.count, Post.where.missing(:author).merge(Author.where(id: 1)).count
+    end
+
     def test_not_inverts_where_clause
       relation = Post.where.not(title: "hello")
       expected_where_clause = Post.where(title: "hello").where_clause.invert