reloading type map on extension changing

activerecord/lib/active_record/connection_adapters/postgresql/oid.rb

@@ -239,6 +239,10 @@ def [](oid)
             @mapping[oid]
           end
 
+          def clear
+            @mapping.clear
+          end
+
           def key?(oid)
             @mapping.key? oid
           end

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -586,11 +586,15 @@ def supports_ranges?
       end
 
       def enable_extension(name)
-        exec_query "CREATE EXTENSION IF NOT EXISTS #{name}"
+        exec_query("CREATE EXTENSION IF NOT EXISTS #{name}").tap {
+          reload_type_map
+        }
       end
 
       def disable_extension(name)
-        exec_query "DROP EXTENSION IF EXISTS #{name} CASCADE"
+        exec_query("DROP EXTENSION IF EXISTS #{name} CASCADE").tap {
+          reload_type_map
+        }
       end
 
       def extension_enabled?(name)
@@ -666,6 +670,11 @@ def translate_exception(exception, message)
 
       private
 
+        def reload_type_map
+          OID::TYPE_MAP.clear
+          initialize_type_map
+        end
+
         def initialize_type_map
           result = execute('SELECT oid, typname, typelem, typdelim, typinput FROM pg_type', 'SCHEMA')
           leaves, nodes = result.partition { |row| row['typelem'] == '0' }