fixes issues with medium size data set speed

simple_survey.install

@@ -127,3 +127,25 @@ function simple_survey_update_9009() {
 
   $manager->installFieldStorageDefinition('submit_button_value', 'survey_question', 'survey_question', $field_storage_definition);
 }
+
+/**
+ * Updates parent uuid field storage definition.
+ */
+function simple_survey_update_10001() {
+  $manager = \Drupal::entityDefinitionUpdateManager();
+
+  if ($field = $manager->getFieldStorageDefinition('parent_uuid', 'survey_answer')) {
+    $manager->updateFieldStorageDefinition($field);
+  }
+}
+
+/**
+ * Updates question idA  field storage definition.
+ */
+function simple_survey_update_10002() {
+  $manager = \Drupal::entityDefinitionUpdateManager();
+
+  if ($field = $manager->getFieldStorageDefinition('question_id', 'survey_answer')) {
+    $manager->updateFieldStorageDefinition($field);
+  }
+}
\ No newline at end of file

src/Form/ExportForm.php

@@ -120,10 +120,27 @@ class ExportForm extends EntityForm {
     ];
 
     if ($form_state->getValue('export_type') == 'csv') {
-      $batch = $this->createCsvBatch($options);
+        $batch = $this->createCsvBatch($options);
     }
     else {
-      $batch = $this->createBqBatch($options);
+
+      /** @var \Drupal\Core\Database\Connection $db */
+      $db = \Drupal::service('database');
+
+      $num_responses = (int) $db->select('survey_response', 'sr')
+          ->condition('sr.survey', $options['survey'])
+          ->condition('sr.sent_to_bq', $options['sent_to_bq'])
+          ->condition('sr.created', strtotime($options['start_date']), '>=')
+          ->condition('sr.created', strtotime($options['end_date']), '<=')
+          ->countQuery()->execute()->fetchField();
+
+      if ($num_responses === 0 && $options['sent_to_bq'] === 0) {
+        $this->messenger()->addWarning('All responses for this date range have been sent. If you want to send them again please select "Export responses that have already been sent to BigQuery".');
+        return FALSE;
+      }
+      else {
+        $batch = $this->createBqBatch($options);
+      }
     }
 
     batch_set($batch);