diff --git a/core/modules/rdf/src/Tests/Field/FieldRdfaTestBase.php b/core/modules/rdf/src/Tests/Field/FieldRdfaTestBase.php
index adddda1..96359ec 100644
--- a/core/modules/rdf/src/Tests/Field/FieldRdfaTestBase.php
+++ b/core/modules/rdf/src/Tests/Field/FieldRdfaTestBase.php
@@ -43,7 +43,7 @@
    *
    * @var bool
    */
-  protected $debug = TRUE;
+  protected $debug = FALSE;
 
   /**
    * Modules to enable.
diff --git a/core/tests/Drupal/Tests/KernelTestBase.php b/core/tests/Drupal/Tests/KernelTestBase.php
index 95b81d5..e923a04 100644
--- a/core/tests/Drupal/Tests/KernelTestBase.php
+++ b/core/tests/Drupal/Tests/KernelTestBase.php
@@ -268,6 +268,38 @@ protected function bootEnvironment() {
     Database::setMultipleConnectionInfo($this->getDatabaseConnectionInfo());
   }
 
+  protected function parseDbUrl($db_url) {
+    $info = parse_url($db_url);
+    if (!isset($info['scheme'], $info['host'], $info['path'])) {
+      throw new \InvalidArgumentException('Invalid dburl, . Minimum requirement: driver://host/database');
+    }
+    $info += [
+      'user' => '',
+      'pass' => '',
+      'fragment' => '',
+    ];
+    if ($info['path'][0] === '/') {
+      $info['path'] = substr($info['path'], 1);
+    }
+    if ($info['scheme'] === 'sqlite' && $info['path'][0] !== '/') {
+      $info['path'] = DRUPAL_ROOT . '/' . $info['path'];
+    }
+    $db_info = [
+      'driver' => $info['scheme'],
+      'username' => $info['user'],
+      'password' => $info['pass'],
+      'host' => $info['host'],
+      'database' => $info['path'],
+      'prefix' => [
+        'default' => $info['fragment'],
+      ],
+    ];
+    if (isset($info['port'])) {
+      $db_info['port'] = $info['port'];
+    }
+    return $db_info;
+  }
+
   /**
    * Bootstraps a kernel for a test.
    */
@@ -401,6 +433,16 @@ protected function getDatabaseConnectionInfo() {
         'default' => '',
       ),
     );
+
+    // Allow to specify a custom db_url.
+    if ($db_url = getenv('phpunit_dburl')) {
+      $databases['default']['default'] = $this->parseDbUrl($db_url);
+
+      // In the case we don't use sqlite directly we need to generate a DB prefix.
+      $suffix = mt_rand(100000, 999999);
+      $this->databasePrefix = 'simpletest' . $suffix;
+      $databases['default']['default']['prefix'] = ['default' => $this->databasePrefix];
+    }
     return $databases;
   }