diff --git a/lib/dev_fixture.php b/lib/dev_fixture.php
index ea344f2..80c5a49 100644
--- a/lib/dev_fixture.php
+++ b/lib/dev_fixture.php
@@ -716,10 +716,17 @@ function qdb_wipe_all_data_except_admins(PDO $pdo): array
 
     $pdo->beginTransaction();
     try {
+        // Interview data references clients/coaches; coach references supervisor.
+        // Disable FK checks for this bulk wipe (same pattern as questionnaire delete).
+        $pdo->exec('PRAGMA foreign_keys = OFF');
+
         $deleted['client_answers'] = (int)$pdo->exec('DELETE FROM client_answer');
         $deleted['completed_questionnaires'] = (int)$pdo->exec('DELETE FROM completed_questionnaire');
         $deleted['clients'] = (int)$pdo->exec('DELETE FROM client');
 
+        $deleted['coaches'] = (int)$pdo->exec('DELETE FROM coach');
+        $deleted['supervisors'] = (int)$pdo->exec('DELETE FROM supervisor');
+
         $sess = $pdo->prepare(
             "DELETE FROM session WHERE userID IN (SELECT userID FROM users WHERE role != 'admin')"
         );
@@ -730,14 +737,16 @@ function qdb_wipe_all_data_except_admins(PDO $pdo): array
         $users->execute();
         $deleted['users'] = $users->rowCount();
 
-        $deleted['coaches'] = (int)$pdo->exec('DELETE FROM coach');
-        $deleted['supervisors'] = (int)$pdo->exec('DELETE FROM supervisor');
-
+        $pdo->exec('PRAGMA foreign_keys = ON');
         $pdo->commit();
     } catch (Throwable $e) {
         if ($pdo->inTransaction()) {
             $pdo->rollBack();
         }
+        try {
+            $pdo->exec('PRAGMA foreign_keys = ON');
+        } catch (Throwable $ignored) {
+        }
         throw $e;
     }