diff --git a/src/Plugin/monitoring/SensorPlugin/DatabaseAggregatorSensorPlugin.php b/src/Plugin/monitoring/SensorPlugin/DatabaseAggregatorSensorPlugin.php
index 6746f51..09c7a5e 100644
--- a/src/Plugin/monitoring/SensorPlugin/DatabaseAggregatorSensorPlugin.php
+++ b/src/Plugin/monitoring/SensorPlugin/DatabaseAggregatorSensorPlugin.php
@@ -443,7 +443,7 @@ class DatabaseAggregatorSensorPlugin extends DatabaseAggregatorSensorPluginBase
 
     // Update the verbose output fields.
     $settings['verbose_fields'] = [];
-    foreach ($form_state->getValue('verbose_fields') as $field) {
+    foreach ($form_state->getValue('verbose_fields', []) as $field) {
       if (!empty($field['field_key'])) {
         $settings['verbose_fields'][] = $field['field_key'];
       }
@@ -544,6 +544,23 @@ class DatabaseAggregatorSensorPlugin extends DatabaseAggregatorSensorPluginBase
           t('The specified time interval field %name does not exist in table %table.', array('%name' => $field_name, '%table' => $table)));
       }
     }
+
+    // Validate verbose_fields.
+    $fields = $form_state->getValue('verbose_fields');
+    foreach ($fields as $key => $field) {
+      $query = $database->select($table);
+      $field_name = $field['field_key'];
+      if (!empty($field_name) && !$database->schema()->fieldExists($table, $field_name)) {
+        $query->addField($table, $field_name);
+        try {
+          $query->range(0, 1)->execute();
+        }
+        catch (\Exception $e) {
+          $form_state->setErrorByName("verbose_fields][$key][field_key", t('The field %field does not exist in the table "%table".', ['%field' => $field_name, '%table' => $table]));
+          continue;
+        }
+      }
+    }
   }
 
 }
diff --git a/src/Plugin/monitoring/SensorPlugin/PhpNoticesSensorPlugin.php b/src/Plugin/monitoring/SensorPlugin/PhpNoticesSensorPlugin.php
index a9c60a5..c7075e9 100644
--- a/src/Plugin/monitoring/SensorPlugin/PhpNoticesSensorPlugin.php
+++ b/src/Plugin/monitoring/SensorPlugin/PhpNoticesSensorPlugin.php
@@ -10,6 +10,7 @@ use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Component\Utility\Xss;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\monitoring\Result\SensorResultInterface;
+use Drupal\monitoring\SensorPlugin\DatabaseAggregatorSensorPluginBase;
 
 /**
  * Displays the most frequent PHP notices and errors.
@@ -122,4 +123,11 @@ class PhpNoticesSensorPlugin extends WatchdogAggregatorSensorPlugin {
     return str_replace(DRUPAL_ROOT . '/', '', $filename);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
+  }
+
+
 }
diff --git a/src/Tests/MonitoringCoreWebTest.php b/src/Tests/MonitoringCoreWebTest.php
index bd1d825..86ebb6a 100644
--- a/src/Tests/MonitoringCoreWebTest.php
+++ b/src/Tests/MonitoringCoreWebTest.php
@@ -63,9 +63,6 @@ class MonitoringCoreWebTest extends MonitoringTestBase {
     $message = (string) $xpath[0]->td[1];
     $this->assertTrue($wid == 14, 'Found WID in verbose output');
     $this->assertTrue($message == 'Session opened for %name.', 'Found unreplaced message in output.');
-    // Test field validation.
-    $this->drupalPostForm('admin/config/system/monitoring/sensors/user_successful_logins', ['verbose_fields[2][field_key]' => 'horstname'], t('Save'));
-    $this->assertText('The field horstname does not exist in the table "watchdog".');
   }
 
   /**
@@ -247,7 +244,6 @@ class MonitoringCoreWebTest extends MonitoringTestBase {
     // Check out sensor result page.
     $this->drupalPostForm('/admin/reports/monitoring/sensors/dblog_php_notices', [], t('Run now'));
     $xpath = $this->xpath('//table[@id="edit-result"]');
-    debug($xpath);
     $header = (array) $xpath[0]->thead->tr->th;
     $body = (array) $xpath[0]->tbody;
     $this->assertEqual($expected_header, $header, 'The header is correct.');