update

Civi/DataProcessor/Source/Contribution/AggregatedContributionSource.php

@@ -86,11 +86,11 @@ class AggregatedContributionSource extends AbstractCivicrmEntitySource {
   public function getAvailableFields() {
     if (!$this->availableFields) {
       $this->availableFields = new DataSpecification();
-      $totalAmount = new FieldSpecification('total_amount', 'Float', E::ts('Total amount'), null);
+      $totalAmount = new FieldSpecification('total_amount', 'Float', E::ts('Total amount'), null, $this->getSourceName().'_total_amount');
       $this->availableFields->addFieldSpecification('total_amount', $totalAmount);
-      $contactId = new FieldSpecification('contact_id', 'Float', E::ts('Contact ID'));
+      $contactId = new FieldSpecification('contact_id', 'Float', E::ts('Contact ID'), null, $this->getSourceName().'_contact_id');
       $this->availableFields->addFieldSpecification('contact_id', $contactId);
-      $count = new FieldSpecification('count', 'Integer', E::ts('Count'), null);
+      $count = new FieldSpecification('count', 'Integer', E::ts('Count'), null, $this->getSourceName().'_count');
       $this->availableFields->addFieldSpecification('count', $count);
     }
     return $this->availableFields;