diff --git a/core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php b/core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php
index 4f18f6a..c3abc02 100644
--- a/core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php
+++ b/core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php
@@ -180,8 +180,8 @@ function checkBinaryOutput() {
    * Verify that a binary data roundtrip returns the original string.
    */
   protected function checkBinaryOutputSuccess() {
-    $bytea_output = db_query("SELECT 'encoding'::bytea AS output")->fetchField();
-    return ($bytea_output == 'encoding');
+    $bytea_output = db_query("SHOW bytea_output")->fetchField();
+    return ($bytea_output == 'escape');
   }
 
   /**
diff --git a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
index 2dd61e5..5422ade 100644
--- a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
+++ b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
@@ -10,9 +10,12 @@
 use Drupal\Component\Utility\Crypt;
 use Drupal\config\Tests\SchemaCheckTestTrait;
 use Drupal\Core\Database\Database;
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\Language\Language;
 use Drupal\Core\Url;
 use Drupal\simpletest\WebTestBase;
 use Drupal\user\Entity\User;
+use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\HttpFoundation\Request;
 
 /**
@@ -141,6 +144,28 @@ function __construct($test_id = NULL) {
    * container that would normally be done via the installer.
    */
   protected function setUp() {
+    // Run the install database tasks. Create a minimal container so that t()
+    // works.
+    // @see install_begin_request()
+    $container = new ContainerBuilder();
+    $container->setParameter('language.default_values', Language::$defaultValues);
+    $container
+      ->register('language.default', 'Drupal\Core\Language\LanguageDefault')
+      ->addArgument('%language.default_values%');
+    $container
+      ->register('language_manager', 'Drupal\Core\Language\LanguageManager')
+      ->addArgument(new Reference('language.default'));
+    $container
+      ->register('string_translation', 'Drupal\Core\StringTranslation\TranslationManager')
+      ->addArgument(new Reference('language_manager'));
+    \Drupal::setContainer($container);
+
+    require_once __DIR__ . '/../../../../../includes/install.inc';
+    $connection = Database::getConnection();
+    $errors = db_installer_object($connection->driver())->runTasks();
+    if (!empty($errors)) {
+      $this->fail('Failed to run installer database tasks: ' . implode(', ', $errors));
+    }
 
     // Allow classes to set database dump files.
     $this->setDatabaseDumpFiles();
diff --git a/core/modules/system/src/Tests/Update/UpdatePathTestBaseFilledTest.php b/core/modules/system/src/Tests/Update/UpdatePathTestBaseFilledTest.php
index 9c175b4..e638745 100644
--- a/core/modules/system/src/Tests/Update/UpdatePathTestBaseFilledTest.php
+++ b/core/modules/system/src/Tests/Update/UpdatePathTestBaseFilledTest.php
@@ -2,7 +2,7 @@
 
 /**
  * @file
- * Contains \Drupal\system\Tests\Update\UpdatePathTestBaseFilledTest.php
+ * Contains \Drupal\system\Tests\Update\UpdatePathTestBaseFilledTest
  */
 
 namespace Drupal\system\Tests\Update;