diff --git a/includes/controller/shifts_controller.php b/includes/controller/shifts_controller.php
index a1801de6..c8b6932a 100644
--- a/includes/controller/shifts_controller.php
+++ b/includes/controller/shifts_controller.php
@@ -316,7 +316,7 @@ function shift_next_controller()
 
     $upcoming_shifts = ShiftEntries_upcoming_for_user($user);
 
-    if (empty($upcoming_shifts)) {
+    if (!empty($upcoming_shifts)) {
         redirect(shift_link($upcoming_shifts[0]));
     }
 
diff --git a/includes/controller/user_driver_licenses_controller.php b/includes/controller/user_driver_licenses_controller.php
index 491a70b2..3098c8ce 100644
--- a/includes/controller/user_driver_licenses_controller.php
+++ b/includes/controller/user_driver_licenses_controller.php
@@ -123,7 +123,7 @@ function user_driver_license_edit_controller()
 
             if (UserDriverLicense_valid($user_driver_license)) {
                 if ($user_driver_license['user_id'] == null) {
-                    $user_driver_license = UserDriverLicenses_create($user_driver_license, $user_source['UID']);
+                    $user_driver_license = UserDriverLicenses_create($user_driver_license, $user_source);
                 } else {
                     UserDriverLicenses_update($user_driver_license);
                 }
@@ -133,7 +133,7 @@ function user_driver_license_edit_controller()
             } else {
                 error(_('Please select at least one driving license.'));
             }
-        } elseif ($user_driver_license['id'] != null) {
+        } elseif ($user_driver_license['user_id'] != null) {
             UserDriverLicenses_delete($user_source['UID']);
             engelsystem_log('Driver license information removed.');
             success(_('Your driver license information has been removed.'));
diff --git a/includes/model/Shifts_model.php b/includes/model/Shifts_model.php
index faa37d59..e2a05c44 100644
--- a/includes/model/Shifts_model.php
+++ b/includes/model/Shifts_model.php
@@ -11,7 +11,7 @@ use Engelsystem\ShiftSignupState;
 function Shifts_by_room($room)
 {
     $result = DB::select('SELECT * FROM `Shifts` WHERE `RID`=? ORDER BY `start`', [$room['RID']]);
-    if (empty($result)) {
+    if (DB::getStm()->errorCode() != '00000') {
         engelsystem_error('Unable to load shifts.');
     }
     return $result;
@@ -23,7 +23,6 @@ function Shifts_by_room($room)
  */
 function Shifts_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
 {
-    //@TODO
     $sql = 'SELECT * FROM (
       SELECT DISTINCT `Shifts`.*, `ShiftTypes`.`name`, `Room`.`Name` AS `room_name`
       FROM `Shifts`
@@ -31,7 +30,7 @@ function Shifts_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
       JOIN `ShiftTypes` ON `ShiftTypes`.`id` = `Shifts`.`shifttype_id`
       JOIN `NeededAngelTypes` ON `NeededAngelTypes`.`shift_id`=`Shifts`.`SID`
       WHERE `Shifts`.`RID` IN (' . implode(',', $shiftsFilter->getRooms()) . ')
-      AND `start` BETWEEN ' . $shiftsFilter->getStartTime() . ' AND ' . $shiftsFilter->getEndTime() . '
+      AND `start` BETWEEN ? AND ?
       AND `NeededAngelTypes`.`angel_type_id` IN (' . implode(',', $shiftsFilter->getTypes()) . ')
       AND `NeededAngelTypes`.`count` > 0
       AND `Shifts`.`PSID` IS NULL
@@ -44,13 +43,21 @@ function Shifts_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
       JOIN `ShiftTypes` ON `ShiftTypes`.`id` = `Shifts`.`shifttype_id`
       JOIN `NeededAngelTypes` ON `NeededAngelTypes`.`room_id`=`Shifts`.`RID`
       WHERE `Shifts`.`RID` IN (' . implode(',', $shiftsFilter->getRooms()) . ')
-      AND `start` BETWEEN ' . $shiftsFilter->getStartTime() . ' AND ' . $shiftsFilter->getEndTime() . '
+      AND `start` BETWEEN ? AND ?
       AND `NeededAngelTypes`.`angel_type_id` IN (' . implode(',', $shiftsFilter->getTypes()) . ')
       AND `NeededAngelTypes`.`count` > 0
       AND NOT `Shifts`.`PSID` IS NULL) AS tmp_shifts
 
       ORDER BY `start`';
-    $result = DB::select($sql);
+    $result = DB::select(
+        $sql,
+        [
+            $shiftsFilter->getStartTime(),
+            $shiftsFilter->getEndTime(),
+            $shiftsFilter->getStartTime(),
+            $shiftsFilter->getEndTime(),
+        ]
+    );
     if (DB::getStm()->errorCode() != '00000') {
         engelsystem_error('Unable to load shifts by filter.');
     }
@@ -63,7 +70,6 @@ function Shifts_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
  */
 function NeededAngeltypes_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
 {
-    //@TODO
     $sql = '
       SELECT
           `NeededAngelTypes`.*,
@@ -76,7 +82,7 @@ function NeededAngeltypes_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
       JOIN `NeededAngelTypes` ON `NeededAngelTypes`.`shift_id`=`Shifts`.`SID`
       JOIN `AngelTypes` ON `AngelTypes`.`id`= `NeededAngelTypes`.`angel_type_id`
       WHERE `Shifts`.`RID` IN (' . implode(',', $shiftsFilter->getRooms()) . ')
-      AND `start` BETWEEN ' . $shiftsFilter->getStartTime() . ' AND ' . $shiftsFilter->getEndTime() . '
+      AND `start` BETWEEN ? AND ?
       AND `Shifts`.`PSID` IS NULL
 
       UNION
@@ -92,9 +98,17 @@ function NeededAngeltypes_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
       JOIN `NeededAngelTypes` ON `NeededAngelTypes`.`room_id`=`Shifts`.`RID`
       JOIN `AngelTypes` ON `AngelTypes`.`id`= `NeededAngelTypes`.`angel_type_id`
       WHERE `Shifts`.`RID` IN (' . implode(',', $shiftsFilter->getRooms()) . ')
-      AND `start` BETWEEN ' . $shiftsFilter->getStartTime() . ' AND ' . $shiftsFilter->getEndTime() . '
+      AND `start` BETWEEN ? AND ?
       AND NOT `Shifts`.`PSID` IS NULL';
-    $result = DB::select($sql);
+    $result = DB::select(
+        $sql,
+        [
+            $shiftsFilter->getStartTime(),
+            $shiftsFilter->getEndTime(),
+            $shiftsFilter->getStartTime(),
+            $shiftsFilter->getEndTime(),
+        ]
+    );
     if (DB::getStm()->errorCode() != '00000') {
         engelsystem_error('Unable to load needed angeltypes by filter.');
     }
@@ -161,7 +175,6 @@ function NeededAngeltype_by_Shift_and_Angeltype($shift, $angeltype)
  */
 function ShiftEntries_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
 {
-    // @TODO
     $sql = '
       SELECT
           `User`.`Nick`,
@@ -178,9 +191,15 @@ function ShiftEntries_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
       JOIN `ShiftEntry` ON `ShiftEntry`.`SID`=`Shifts`.`SID`
       JOIN `User` ON `ShiftEntry`.`UID`=`User`.`UID`
       WHERE `Shifts`.`RID` IN (' . implode(',', $shiftsFilter->getRooms()) . ')
-      AND `start` BETWEEN ' . $shiftsFilter->getStartTime() . ' AND ' . $shiftsFilter->getEndTime() . '
+      AND `start` BETWEEN ? AND ?
       ORDER BY `Shifts`.`start`';
-    $result = DB::select($sql);
+    $result = DB::select(
+        $sql,
+        [
+            $shiftsFilter->getStartTime(),
+            $shiftsFilter->getEndTime(),
+        ]
+    );
     if (DB::getStm()->errorCode() != '00000') {
         engelsystem_error('Unable to load shift entries by filter.');
     }
diff --git a/includes/pages/admin_user.php b/includes/pages/admin_user.php
index 60349676..8f833087 100644
--- a/includes/pages/admin_user.php
+++ b/includes/pages/admin_user.php
@@ -45,7 +45,7 @@ function admin_user()
             . 'Wenn T-Shirt ein \'Ja\' enthält, bedeutet dies, dass der Engel '
             . 'bereits sein T-Shirt erhalten hat.<br /><br />' . "\n";
 
-        $html .= '<form action="' . page_link_to('admin_user') . '&action=save&id=$user_id" method="post">' . "\n";
+        $html .= '<form action="' . page_link_to('admin_user') . '&action=save&id=' . $user_id . '" method="post">' . "\n";
         $html .= '<table border="0">' . "\n";
         $html .= '<input type="hidden" name="Type" value="Normal">' . "\n";
         $html .= '<tr><td>' . "\n";