diff --git a/includes/model/Shifts_model.php b/includes/model/Shifts_model.php
index a1d7967f..28f84c26 100644
--- a/includes/model/Shifts_model.php
+++ b/includes/model/Shifts_model.php
@@ -1,5 +1,19 @@
 <?php
 
+/**
+ * Delete a shift by its external id.
+ */
+function Shift_delete_by_psid($shift_psid) {
+  return sql_query("DELETE FROM `Shifts` WHERE `PSID`=" . sql_escape($shift_psid));
+}
+
+/**
+ * Delete a shift.
+ */
+function Shift_delete($shift_id) {
+  return sql_query("DELETE FROM `Shifts` WHERE `SID`=" . sql_escape($shift_id));
+}
+
 /**
  * Update a shift.
  */
diff --git a/includes/pages/admin_import.php b/includes/pages/admin_import.php
index f4c2b252..120ab91b 100644
--- a/includes/pages/admin_import.php
+++ b/includes/pages/admin_import.php
@@ -129,8 +129,11 @@ function admin_import() {
           engelsystem_error('Unable to update shift.');
       }
       
-      foreach ($events_deleted as $event)
-        sql_query("DELETE FROM `Shifts` WHERE `PSID`=" . sql_escape($event['PSID']) . " LIMIT 1");
+      foreach ($events_deleted as $event) {
+        $result = Shift_delete_by_psid($event['PSID']);
+        if ($result === false)
+          engelsystem_error('Unable to delete shift.');
+      }
       
       engelsystem_log("Pentabarf import done");
       
diff --git a/includes/pages/user_shifts.php b/includes/pages/user_shifts.php
index 2f0bee6e..c1a5cc91 100644
--- a/includes/pages/user_shifts.php
+++ b/includes/pages/user_shifts.php
@@ -178,8 +178,9 @@ function user_shifts() {
     
     // Schicht löschen bestätigt
     if (isset($_REQUEST['delete'])) {
-      sql_query("DELETE FROM `NeededAngelTypes` WHERE `shift_id`=" . sql_escape($shift_id));
-      sql_query("DELETE FROM `Shifts` WHERE `SID`=" . sql_escape($shift_id) . " LIMIT 1");
+      $result = Shift_delete($shift_id);
+      if ($result === false)
+        engelsystem_error('Unable to delete shift.');
       
       engelsystem_log("Deleted shift " . $shift['name'] . " from " . date("y-m-d H:i", $shift['start']) . " to " . date("y-m-d H:i", $shift['end']));
       success(_("Shift deleted."));