1 files changed, 70 insertions, 2 deletions
diff --git a/activerecord/lib/active_record/table_metadata.rb b/activerecord/lib/active_record/table_metadata.rb
index 811e6964a9..e60bf55021 100644
--- a/activerecord/lib/active_record/table_metadata.rb
+++ b/activerecord/lib/active_record/table_metadata.rb
@@ -33,12 +33,19 @@ module ActiveRecord
     end
 
     def associated_table(table_name)
+      return self if table_name == arel_table.name
+
       arel_table = Arel::Table.new(table_name)
       association = klass._reflect_on_association(table_name)
       if association && !association.polymorphic?
-        klass = association.klass
+        association_klass = association.klass
+      end
+
+      if association
+        TableMetadata.new(association_klass, arel_table, association)
+      else
+        ConnectionAdapterTable.new(klass.connection, arel_table)
       end
-      TableMetadata.new(klass, arel_table, association)
     end
 
     def polymorphic_association?
@@ -49,4 +56,65 @@ module ActiveRecord
 
     attr_reader :klass, :arel_table, :association
   end
+
+  # FIXME: We want to get rid of this class. The connection adapter does not
+  # have sufficient knowledge about types, as they could be provided by or
+  # overriden by the ActiveRecord::Base subclass. The case where you reach this
+  # class is if you do a query like:
+  #
+  #     Liquid.joins(molecules: :electrons)
+  #       .where("molecules.name" => "something", "electrons.name" => "something")
+  #
+  # Since we don't know that we can get to electrons through molecules
+  class ConnectionAdapterTable # :nodoc:
+    def initialize(connection, arel_table)
+      @connection = connection
+      @arel_table = arel_table
+    end
+
+    def type_cast_for_database(attribute_name, value)
+      return value if value.is_a?(Arel::Nodes::BindParam)
+      type = type_for(attribute_name)
+      Arel::Nodes::Quoted.new(type.type_cast_for_database(value))
+    end
+
+    def resolve_column_aliases(hash)
+      hash
+    end
+
+    def arel_attribute(column_name)
+      arel_table[column_name]
+    end
+
+    def associated_with?(*)
+      false
+    end
+
+    def associated_table(table_name)
+      arel_table = Arel::Table.new(table_name)
+      ConnectionAdapterTable.new(klass.connection, arel_table)
+    end
+
+    def polymorphic_association?
+      false
+    end
+
+    protected
+
+    attr_reader :connection, :arel_table
+
+    private
+
+    def type_for(attribute_name)
+      if connection.schema_cache.table_exists?(arel_table.name)
+        column_for(attribute_name).cast_type
+      else
+        Type::Value.new
+      end
+    end
+
+    def column_for(attribute_name)
+      connection.schema_cache.columns_hash(arel_table.name)[attribute_name.to_s]
+    end
+  end
 end