diff --git a/includes/controller/shift_entries_controller.php b/includes/controller/shift_entries_controller.php
index 03d7a27f..72189869 100644
--- a/includes/controller/shift_entries_controller.php
+++ b/includes/controller/shift_entries_controller.php
@@ -43,7 +43,7 @@ function shift_entry_add_controller()
         $type = AngelType($type_id);
     } else {
         // TODO: Move queries to model
-        $type = DB::select('
+        $type = DB::selectOne('
             SELECT *
             FROM `UserAngelTypes`
             JOIN `AngelTypes` ON (`UserAngelTypes`.`angeltype_id` = `AngelTypes`.`id`)
@@ -56,7 +56,6 @@ function shift_entry_add_controller()
                 )
             )
         ', [$type_id, $user['UID']]);
-        $type = array_shift($type);
     }
 
     if (empty($type)) {
@@ -241,7 +240,7 @@ function shift_entry_delete_controller()
     }
     $entry_id = $request->input('entry_id');
 
-    $shift_entry_source = DB::select('
+    $shift_entry_source = DB::selectOne('
         SELECT
             `User`.`Nick`,
             `ShiftEntry`.`Comment`,
@@ -260,9 +259,7 @@ function shift_entry_delete_controller()
         WHERE `ShiftEntry`.`id`=?',
         [$entry_id]
     );
-    if (count($shift_entry_source) > 0) {
-        $shift_entry_source = array_shift($shift_entry_source);
-
+    if (!empty($shift_entry_source)) {
         if (!in_array('user_shifts_admin', $privileges) && (!in_array('shiftentry_edit_angeltype_supporter',
                     $privileges) || !User_is_AngelType_supporter($user, AngelType($shift_entry_source['angeltype_id'])))
         ) {
diff --git a/includes/model/AngelType_model.php b/includes/model/AngelType_model.php
index f08733d5..bc535667 100644
--- a/includes/model/AngelType_model.php
+++ b/includes/model/AngelType_model.php
@@ -256,14 +256,8 @@ function AngelType_ids()
  */
 function AngelType($angeltype_id)
 {
-    $angelType_source = DB::select(
+    return DB::selectOne(
         'SELECT * FROM `AngelTypes` WHERE `id`=?',
         [$angeltype_id]
     );
-
-    if (empty($angelType_source)) {
-        return null;
-    }
-
-    return array_shift($angelType_source);
 }
diff --git a/includes/model/EventConfig_model.php b/includes/model/EventConfig_model.php
index c5caf4d5..646d19c5 100644
--- a/includes/model/EventConfig_model.php
+++ b/includes/model/EventConfig_model.php
@@ -9,13 +9,7 @@ use Engelsystem\Database\DB;
  */
 function EventConfig()
 {
-    $event_config = DB::select('SELECT * FROM `EventConfig` LIMIT 1');
-
-    if (empty($event_config)) {
-        return null;
-    }
-
-    return array_shift($event_config);
+    return DB::selectOne('SELECT * FROM `EventConfig` LIMIT 1');
 }
 
 /**
diff --git a/includes/model/Message_model.php b/includes/model/Message_model.php
index ebd4b37e..9bb037af 100644
--- a/includes/model/Message_model.php
+++ b/includes/model/Message_model.php
@@ -20,11 +20,7 @@ function Message_ids()
  */
 function Message($message_id)
 {
-    $message_source = DB::select('SELECT * FROM `Messages` WHERE `id`=? LIMIT 1', [$message_id]);
-    if (empty($message_source)) {
-        return null;
-    }
-    return array_shift($message_source);
+    return DB::selectOne('SELECT * FROM `Messages` WHERE `id`=? LIMIT 1', [$message_id]);
 }
 
 /**
diff --git a/includes/model/Room_model.php b/includes/model/Room_model.php
index 08e0f7bf..8425e5ad 100644
--- a/includes/model/Room_model.php
+++ b/includes/model/Room_model.php
@@ -58,17 +58,11 @@ function Room_create($name, $from_frab, $public, $number = null)
  */
 function Room($room_id, $onlyVisible = true)
 {
-    $room_source = DB::select('
+    return DB::selectOne('
         SELECT *
         FROM `Room`
         WHERE `RID` = ?
         ' . ($onlyVisible ? 'AND `show` = \'Y\'' : ''),
         [$room_id]
     );
-
-    if (empty($room_source)) {
-        return null;
-    }
-
-    return array_shift($room_source);
 }
diff --git a/includes/model/ShiftEntry_model.php b/includes/model/ShiftEntry_model.php
index 563a611f..3a7254ad 100644
--- a/includes/model/ShiftEntry_model.php
+++ b/includes/model/ShiftEntry_model.php
@@ -28,10 +28,9 @@ function ShiftEntry_new()
  */
 function ShiftEntries_freeleaded_count()
 {
-    $result = DB::select('SELECT COUNT(*) FROM `ShiftEntry` WHERE `freeloaded` = 1');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT COUNT(*) FROM `ShiftEntry` WHERE `freeloaded` = 1');
 
-    if (!is_array($result)) {
+    if (empty($result)) {
         return 0;
     }
 
@@ -129,13 +128,7 @@ function ShiftEntry_update($shift_entry)
  */
 function ShiftEntry($shift_entry_id)
 {
-    $shift_entry = DB::select('SELECT * FROM `ShiftEntry` WHERE `id` = ?', [$shift_entry_id]);
-
-    if (empty($shift_entry)) {
-        return null;
-    }
-
-    return $shift_entry[0];
+    return DB::selectOne('SELECT * FROM `ShiftEntry` WHERE `id` = ?', [$shift_entry_id]);
 }
 
 /**
diff --git a/includes/model/ShiftTypes_model.php b/includes/model/ShiftTypes_model.php
index 05c1a949..227df367 100644
--- a/includes/model/ShiftTypes_model.php
+++ b/includes/model/ShiftTypes_model.php
@@ -70,13 +70,7 @@ function ShiftType_create($name, $angeltype_id, $description)
  */
 function ShiftType($shifttype_id)
 {
-    $shifttype = DB::select('SELECT * FROM `ShiftTypes` WHERE `id`=?', [$shifttype_id]);
-
-    if (empty($shifttype)) {
-        return null;
-    }
-
-    return array_shift($shifttype);
+    return DB::selectOne('SELECT * FROM `ShiftTypes` WHERE `id`=?', [$shifttype_id]);
 }
 
 /**
diff --git a/includes/model/Shifts_model.php b/includes/model/Shifts_model.php
index 939a4f4e..88b28998 100644
--- a/includes/model/Shifts_model.php
+++ b/includes/model/Shifts_model.php
@@ -112,7 +112,7 @@ function NeededAngeltypes_by_ShiftsFilter(ShiftsFilter $shiftsFilter)
  */
 function NeededAngeltype_by_Shift_and_Angeltype($shift, $angeltype)
 {
-    $result = DB::select('
+    return DB::selectOne('
           SELECT
               `NeededAngelTypes`.*,
               `Shifts`.`SID`,
@@ -150,12 +150,6 @@ function NeededAngeltype_by_Shift_and_Angeltype($shift, $angeltype)
             $angeltype['id']
         ]
     );
-
-    if (empty($result)) {
-        return null;
-    }
-
-    return $result[0];
 }
 
 /**
@@ -453,13 +447,13 @@ function Shift_update($shift)
  */
 function Shift_update_by_psid($shift)
 {
-    $shift_source = DB::select('SELECT `SID` FROM `Shifts` WHERE `PSID`=?', [$shift['PSID']]);
+    $shift_source = DB::selectOne('SELECT `SID` FROM `Shifts` WHERE `PSID`=?', [$shift['PSID']]);
 
     if (empty($shift_source)) {
         throw new Exception('Shift not found.');
     }
 
-    $shift['SID'] = $shift_source[0]['SID'];
+    $shift['SID'] = $shift_source['SID'];
     return Shift_update($shift);
 }
 
@@ -537,18 +531,16 @@ function Shifts_by_user($user, $include_freeload_comments = false)
  */
 function Shift($shift_id)
 {
-    $shifts_source = DB::select('
+    $result = DB::selectOne('
       SELECT `Shifts`.*, `ShiftTypes`.`name`
       FROM `Shifts`
       JOIN `ShiftTypes` ON (`ShiftTypes`.`id` = `Shifts`.`shifttype_id`)
       WHERE `SID`=?', [$shift_id]);
 
-    if (empty($shifts_source)) {
+    if (empty($result)) {
         return null;
     }
 
-    $result = $shifts_source[0];
-
     $shiftsEntry_source = DB::select('
         SELECT `id`, `TID` , `UID` , `freeloaded`
         FROM `ShiftEntry`
diff --git a/includes/model/UserAngelTypes_model.php b/includes/model/UserAngelTypes_model.php
index 3ec151fb..5b0caf98 100644
--- a/includes/model/UserAngelTypes_model.php
+++ b/includes/model/UserAngelTypes_model.php
@@ -197,17 +197,11 @@ function UserAngelType_create($user, $angeltype)
  */
 function UserAngelType($user_angeltype_id)
 {
-    $angeltype = DB::select('
+    return DB::selectOne('
       SELECT *
       FROM `UserAngelTypes`
       WHERE `id`=?
       LIMIT 1', [$user_angeltype_id]);
-
-    if (empty($angeltype)) {
-        return null;
-    }
-
-    return $angeltype[0];
 }
 
 /**
@@ -219,7 +213,7 @@ function UserAngelType($user_angeltype_id)
  */
 function UserAngelType_by_User_and_AngelType($user, $angeltype)
 {
-    $angeltype = DB::select('
+    return DB::selectOne('
           SELECT *
           FROM `UserAngelTypes`
           WHERE `user_id`=?
@@ -231,10 +225,4 @@ function UserAngelType_by_User_and_AngelType($user, $angeltype)
             $angeltype['id']
         ]
     );
-
-    if (empty($angeltype)) {
-        return null;
-    }
-
-    return array_shift($angeltype);
 }
diff --git a/includes/model/UserDriverLicenses_model.php b/includes/model/UserDriverLicenses_model.php
index 515a2701..798aa6ab 100644
--- a/includes/model/UserDriverLicenses_model.php
+++ b/includes/model/UserDriverLicenses_model.php
@@ -45,16 +45,10 @@ function UserDriverLicense_valid($user_driver_license)
  */
 function UserDriverLicense($user_id)
 {
-    $user_driver_license = DB::select('
+    return DB::selectOne('
         SELECT *
         FROM `UserDriverLicenses`
         WHERE `user_id`=?', [$user_id]);
-
-    if (empty($user_driver_license)) {
-        return null;
-    }
-
-    return array_shift($user_driver_license);
 }
 
 /**
diff --git a/includes/model/User_model.php b/includes/model/User_model.php
index f86d5bf6..4757ed3c 100644
--- a/includes/model/User_model.php
+++ b/includes/model/User_model.php
@@ -87,8 +87,7 @@ function User_update($user)
  */
 function User_force_active_count()
 {
-    $result = DB::select('SELECT COUNT(*) FROM `User` WHERE `force_active` = 1');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT COUNT(*) FROM `User` WHERE `force_active` = 1');
 
     if (empty($result)) {
         return 0;
@@ -102,8 +101,7 @@ function User_force_active_count()
  */
 function User_active_count()
 {
-    $result = DB::select('SELECT COUNT(*) FROM `User` WHERE `Aktiv` = 1');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT COUNT(*) FROM `User` WHERE `Aktiv` = 1');
 
     if (empty($result)) {
         return 0;
@@ -117,8 +115,7 @@ function User_active_count()
  */
 function User_got_voucher_count()
 {
-    $result = DB::select('SELECT SUM(`got_voucher`) FROM `User`');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT SUM(`got_voucher`) FROM `User`');
 
     if (empty($result)) {
         return 0;
@@ -132,8 +129,7 @@ function User_got_voucher_count()
  */
 function User_arrived_count()
 {
-    $result = DB::select('SELECT COUNT(*) FROM `User` WHERE `Gekommen` = 1');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT COUNT(*) FROM `User` WHERE `Gekommen` = 1');
 
     if (empty($result)) {
         return 0;
@@ -147,8 +143,7 @@ function User_arrived_count()
  */
 function User_tshirts_count()
 {
-    $result = DB::select('SELECT COUNT(*) FROM `User` WHERE `Tshirt` = 1');
-    $result = array_shift($result);
+    $result = DB::selectOne('SELECT COUNT(*) FROM `User` WHERE `Tshirt` = 1');
 
     if (empty($result)) {
         return 0;
@@ -382,13 +377,7 @@ function User_validate_planned_departure_date($planned_arrival_date, $planned_de
  */
 function User($user_id)
 {
-    $user_source = DB::select('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$user_id]);
-
-    if (empty($user_source)) {
-        return null;
-    }
-
-    return array_shift($user_source);
+    return DB::selectOne('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$user_id]);
 }
 
 /**
@@ -400,13 +389,7 @@ function User($user_id)
  */
 function User_by_api_key($api_key)
 {
-    $user = DB::select('SELECT * FROM `User` WHERE `api_key`=? LIMIT 1', [$api_key]);
-
-    if (empty($user)) {
-        return null;
-    }
-
-    return $user[0];
+    return DB::selectOne('SELECT * FROM `User` WHERE `api_key`=? LIMIT 1', [$api_key]);
 }
 
 /**
@@ -417,30 +400,18 @@ function User_by_api_key($api_key)
  */
 function User_by_email($email)
 {
-    $user = DB::select('SELECT * FROM `User` WHERE `email`=? LIMIT 1', [$email]);
-
-    if (empty($user)) {
-        return null;
-    }
-
-    return array_shift($user);
+    return DB::selectOne('SELECT * FROM `User` WHERE `email`=? LIMIT 1', [$email]);
 }
 
 /**
  * Returns User by password token.
  *
  * @param string $token
- * @return array|null Matching user, null or false on error
+ * @return array|null Matching user, null when not found
  */
 function User_by_password_recovery_token($token)
 {
-    $user = DB::select('SELECT * FROM `User` WHERE `password_recovery_token`=? LIMIT 1', [$token]);
-
-    if (empty($user)) {
-        return null;
-    }
-
-    return array_shift($user);
+    return DB::selectOne('SELECT * FROM `User` WHERE `password_recovery_token`=? LIMIT 1', [$token]);
 }
 
 /**
diff --git a/includes/pages/admin_active.php b/includes/pages/admin_active.php
index 2e06f90d..be1217ff 100644
--- a/includes/pages/admin_active.php
+++ b/includes/pages/admin_active.php
@@ -210,19 +210,17 @@ function admin_active()
     $shirt_statistics = [];
     foreach (array_keys($tshirt_sizes) as $size) {
         if (!empty($size)) {
-            $sc = DB::select(
+            $sc = DB::selectOne(
                 'SELECT count(*) FROM `User` WHERE `Size`=? AND `Gekommen`=1',
                 [$size]
             );
             $sc = array_shift($sc);
-            $sc = array_shift($sc);
 
-            $gc = DB::select(
+            $gc = DB::selectOne(
                 'SELECT count(*) FROM `User` WHERE `Size`=? AND `Tshirt`=1',
                 [$size]
             );
             $gc = array_shift($gc);
-            $gc = array_shift($gc);
 
             $shirt_statistics[] = [
                 'size'   => $size,
@@ -232,8 +230,7 @@ function admin_active()
         }
     }
 
-    $uc = DB::select('SELECT count(*) FROM `User` WHERE `Tshirt`=1');
-    $uc = array_shift($uc);
+    $uc = DB::selectOne('SELECT count(*) FROM `User` WHERE `Tshirt`=1');
     $uc = array_shift($uc);
 
     $shirt_statistics[] = [
diff --git a/includes/pages/admin_groups.php b/includes/pages/admin_groups.php
index c483a79d..ea0d4dbc 100644
--- a/includes/pages/admin_groups.php
+++ b/includes/pages/admin_groups.php
@@ -107,23 +107,21 @@ function admin_groups()
                     return error('Incomplete call, missing Groups ID.', true);
                 }
 
-                $group = DB::select('SELECT * FROM `Groups` WHERE `UID`=? LIMIT 1', [$group_id]);
+                $group = DB::selectOne('SELECT * FROM `Groups` WHERE `UID`=? LIMIT 1', [$group_id]);
                 $privileges = $request->get('privileges');
                 if (!is_array($privileges)) {
                     $privileges = [];
                 }
                 if (!empty($group)) {
-                    $group = array_shift($group);
                     DB::delete('DELETE FROM `GroupPrivileges` WHERE `group_id`=?', [$group_id]);
                     $privilege_names = [];
                     foreach ($privileges as $privilege) {
                         if (preg_match('/^\d{1,}$/', $privilege)) {
-                            $group_privileges_source = DB::select(
+                            $group_privileges_source = DB::selectOne(
                                 'SELECT `name` FROM `Privileges` WHERE `id`=? LIMIT 1',
                                 [$privilege]
                             );
                             if (!empty($group_privileges_source)) {
-                                $group_privileges_source = array_shift($group_privileges_source);
                                 DB::insert(
                                     'INSERT INTO `GroupPrivileges` (`group_id`, `privilege_id`) VALUES (?, ?)',
                                     [$group_id, $privilege]
diff --git a/includes/pages/admin_news.php b/includes/pages/admin_news.php
index 7f8ca1ba..4eafd3e2 100644
--- a/includes/pages/admin_news.php
+++ b/includes/pages/admin_news.php
@@ -21,14 +21,13 @@ function admin_news()
         return error('Incomplete call, missing News ID.', true);
     }
 
-    $news = DB::select('SELECT * FROM `News` WHERE `ID`=? LIMIT 1', [$news_id]);
+    $news = DB::selectOne('SELECT * FROM `News` WHERE `ID`=? LIMIT 1', [$news_id]);
     if (empty($news)) {
         return error('No News found.', true);
     }
 
     switch ($request->input('action')) {
         case 'edit':
-            $news = array_shift($news);
             $user_source = User($news['UID']);
 
             $html .= form([
@@ -70,7 +69,6 @@ function admin_news()
             break;
 
         case 'delete':
-            $news = array_shift($news);
             DB::delete('DELETE FROM `News` WHERE `ID`=? LIMIT 1', [$news_id]);
             engelsystem_log('News deleted: ' . $news['Betreff']);
             success(_('News entry deleted.'));
diff --git a/includes/pages/admin_questions.php b/includes/pages/admin_questions.php
index d05bace6..2b61b055 100644
--- a/includes/pages/admin_questions.php
+++ b/includes/pages/admin_questions.php
@@ -105,11 +105,11 @@ function admin_questions()
                     return error('Incomplete call, missing Question ID.', true);
                 }
 
-                $question = DB::select(
+                $question = DB::selectOne(
                     'SELECT * FROM `Questions` WHERE `QID`=? LIMIT 1',
                     [$question_id]
                 );
-                if (count($question) > 0 && $question[0]['AID'] == null) {
+                if (!empty($question) && $question['AID'] == null) {
                     $answer = trim(
                         preg_replace("/([^\p{L}\p{P}\p{Z}\p{N}\n]{1,})/ui",
                             '',
@@ -129,7 +129,7 @@ function admin_questions()
                                 $question_id,
                             ]
                         );
-                        engelsystem_log('Question ' . $question[0]['Question'] . ' answered: ' . $answer);
+                        engelsystem_log('Question ' . $question['Question'] . ' answered: ' . $answer);
                         redirect(page_link_to('admin_questions'));
                     } else {
                         return error('Enter an answer!', true);
@@ -145,13 +145,13 @@ function admin_questions()
                     return error('Incomplete call, missing Question ID.', true);
                 }
 
-                $question = DB::select(
+                $question = DB::selectOne(
                     'SELECT * FROM `Questions` WHERE `QID`=? LIMIT 1',
                     [$question_id]
                 );
-                if (count($question) > 0) {
+                if (!empty($question)) {
                     DB::delete('DELETE FROM `Questions` WHERE `QID`=? LIMIT 1', [$question_id]);
-                    engelsystem_log('Question deleted: ' . $question[0]['Question']);
+                    engelsystem_log('Question deleted: ' . $question['Question']);
                     redirect(page_link_to('admin_questions'));
                 } else {
                     return error('No question found.', true);
diff --git a/includes/pages/admin_shifts.php b/includes/pages/admin_shifts.php
index 36028792..b5079ed1 100644
--- a/includes/pages/admin_shifts.php
+++ b/includes/pages/admin_shifts.php
@@ -325,7 +325,7 @@ function admin_shifts()
             );
 
             foreach ($_SESSION['admin_shifts_types'] as $type_id => $count) {
-                $angel_type_source = DB::select('
+                $angel_type_source = DB::selectOne('
                       SELECT *
                       FROM `AngelTypes`
                       WHERE `id` = ?
@@ -341,7 +341,7 @@ function admin_shifts()
                             $count
                         ]
                     );
-                    $needed_angel_types_info[] = $angel_type_source[0]['name'] . ': ' . $count;
+                    $needed_angel_types_info[] = $angel_type_source['name'] . ': ' . $count;
                 }
             }
         }
diff --git a/includes/pages/admin_user.php b/includes/pages/admin_user.php
index 510e2292..6bdc8d71 100644
--- a/includes/pages/admin_user.php
+++ b/includes/pages/admin_user.php
@@ -116,20 +116,20 @@ function admin_user()
 
         $html .= '<hr />';
 
-        $my_highest_group = DB::select(
+        $my_highest_group = DB::selectOne(
             'SELECT group_id FROM `UserGroups` WHERE `uid`=? ORDER BY `group_id` LIMIT 1',
             [$user['UID']]
         );
-        if (count($my_highest_group) > 0) {
-            $my_highest_group = $my_highest_group[0]['group_id'];
+        if (!empty($my_highest_group)) {
+            $my_highest_group = $my_highest_group['group_id'];
         }
 
-        $his_highest_group = DB::select(
+        $his_highest_group = DB::selectOne(
             'SELECT `group_id` FROM `UserGroups` WHERE `uid`=? ORDER BY `group_id` LIMIT 1',
             [$user_id]
         );
-        if (count($his_highest_group) > 0) {
-            $his_highest_group = $his_highest_group[0]['group_id'];
+        if (!empty($his_highest_group)) {
+            $his_highest_group = $his_highest_group['group_id'];
         }
 
         if ($user_id != $user['UID'] && $my_highest_group <= $his_highest_group) {
@@ -188,7 +188,7 @@ function admin_user()
                         count($my_highest_group) > 0
                         && (
                             count($his_highest_group) == 0
-                            || ($my_highest_group[0]['group_id'] <= $his_highest_group[0]['group_id'])
+                            || ($my_highest_group['group_id'] <= $his_highest_group['group_id'])
                         )
                     ) {
                         $groups_source = DB::select('
@@ -203,7 +203,7 @@ function admin_user()
                             ',
                             [
                                 $user_id,
-                                $my_highest_group[0]['group_id'],
+                                $my_highest_group['group_id'],
                             ]
                         );
                         $groups = [];
diff --git a/includes/pages/guest_login.php b/includes/pages/guest_login.php
index 106db33a..f8c52767 100644
--- a/includes/pages/guest_login.php
+++ b/includes/pages/guest_login.php
@@ -399,9 +399,8 @@ function guest_login()
     if ($request->has('submit')) {
         if ($request->has('nick') && strlen(User_validate_Nick($request->input('nick'))) > 0) {
             $nick = User_validate_Nick($request->input('nick'));
-            $login_user = DB::select('SELECT * FROM `User` WHERE `Nick`=?', [$nick]);
-            if (count($login_user) > 0) {
-                $login_user = $login_user[0];
+            $login_user = DB::selectOne('SELECT * FROM `User` WHERE `Nick`=?', [$nick]);
+            if (!empty($login_user)) {
                 if ($request->has('password')) {
                     if (!verify_password($request->post('password'), $login_user['Passwort'], $login_user['UID'])) {
                         $valid = false;
diff --git a/includes/pages/guest_stats.php b/includes/pages/guest_stats.php
index 8aa6f740..bf1814a3 100644
--- a/includes/pages/guest_stats.php
+++ b/includes/pages/guest_stats.php
@@ -17,13 +17,12 @@ function guest_stats()
             list($arrived_user_count) = DB::select('SELECT count(*) AS `user_count` FROM `User` WHERE `Gekommen`=1');
             $stats['arrived_user_count'] = $arrived_user_count['user_count'];
 
-            $done_shifts_seconds = DB::select('
+            $done_shifts_seconds = DB::selectOne('
                 SELECT SUM(`Shifts`.`end` - `Shifts`.`start`)
                 FROM `ShiftEntry`
                 JOIN `Shifts` USING (`SID`)
                 WHERE `Shifts`.`end` < UNIX_TIMESTAMP()
             ');
-            $done_shifts_seconds = array_shift($done_shifts_seconds);
             $done_shifts_seconds = (int)array_shift($done_shifts_seconds);
             $stats['done_work_hours'] = round($done_shifts_seconds / (60 * 60), 0);
 
diff --git a/includes/pages/user_messages.php b/includes/pages/user_messages.php
index a811970d..2dea6207 100644
--- a/includes/pages/user_messages.php
+++ b/includes/pages/user_messages.php
@@ -130,11 +130,11 @@ function user_messages()
                     return error(_('Incomplete call, missing Message ID.'), true);
                 }
 
-                $message = DB::select(
+                $message = DB::selectOne(
                     'SELECT `RUID` FROM `Messages` WHERE `id`=? LIMIT 1',
                     [$message_id]
                 );
-                if (count($message) > 0 && $message[0]['RUID'] == $user['UID']) {
+                if (!empty($message) && $message['RUID'] == $user['UID']) {
                     DB::update(
                         'UPDATE `Messages` SET `isRead`=\'Y\' WHERE `id`=? LIMIT 1',
                         [$message_id]
@@ -152,11 +152,11 @@ function user_messages()
                     return error(_('Incomplete call, missing Message ID.'), true);
                 }
 
-                $message = DB::select(
+                $message = DB::selectOne(
                     'SELECT `SUID` FROM `Messages` WHERE `id`=? LIMIT 1',
                     [$message_id]
                 );
-                if (count($message) > 0 && $message[0]['SUID'] == $user['UID']) {
+                if (!empty($message) && $message['SUID'] == $user['UID']) {
                     DB::delete('DELETE FROM `Messages` WHERE `id`=? LIMIT 1', [$message_id]);
                     redirect(page_link_to('user_messages'));
                 } else {
diff --git a/includes/pages/user_myshifts.php b/includes/pages/user_myshifts.php
index a10e6f82..81f8f505 100644
--- a/includes/pages/user_myshifts.php
+++ b/includes/pages/user_myshifts.php
@@ -31,8 +31,7 @@ function user_myshifts()
         $user_id = $user['UID'];
     }
 
-    $shifts_user = DB::select('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$user_id]);
-    $shifts_user = array_shift($shifts_user);
+    $shifts_user = DB::selectOne('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$user_id]);
 
     if ($request->has('reset')) {
         if ($request->input('reset') == 'ack') {
@@ -49,7 +48,7 @@ function user_myshifts()
         ]);
     } elseif ($request->has('edit') && preg_match('/^\d*$/', $request->input('edit'))) {
         $user_id = $request->input('edit');
-        $shift = DB::select('
+        $shift = DB::selectOne('
                 SELECT
                     `ShiftEntry`.`freeloaded`,
                     `ShiftEntry`.`freeload_comment`,
@@ -74,7 +73,6 @@ function user_myshifts()
             ]
         );
         if (count($shift) > 0) {
-            $shift = array_shift($shift);
             $freeloaded = $shift['freeloaded'];
             $freeload_comment = $shift['freeload_comment'];
 
@@ -128,7 +126,7 @@ function user_myshifts()
         }
     } elseif ($request->has('cancel') && preg_match('/^\d*$/', $request->input('cancel'))) {
         $user_id = $request->input('cancel');
-        $shift = DB::select('
+        $shift = DB::selectOne('
                 SELECT *
                 FROM `Shifts`
                 INNER JOIN `ShiftEntry` USING (`SID`)
@@ -140,7 +138,6 @@ function user_myshifts()
             ]
         );
         if (count($shift) > 0) {
-            $shift = array_shift($shift);
             if (
                 ($shift['start'] > time() + config('last_unsubscribe') * 3600)
                 || in_array('user_shifts_admin', $privileges)
diff --git a/includes/pages/user_news.php b/includes/pages/user_news.php
index 9bdcb6fb..3cf11a6b 100644
--- a/includes/pages/user_news.php
+++ b/includes/pages/user_news.php
@@ -126,8 +126,7 @@ function user_news_comments()
         && count(DB::select('SELECT `ID` FROM `News` WHERE `ID`=? LIMIT 1', [$request->input('nid')])) > 0
     ) {
         $nid = $request->input('nid');
-        $news = DB::select('SELECT * FROM `News` WHERE `ID`=? LIMIT 1', [$nid]);
-        $news = array_shift($news);
+        $news = DB::selectOne('SELECT * FROM `News` WHERE `ID`=? LIMIT 1', [$nid]);
         if ($request->has('text')) {
             $text = preg_replace("/([^\p{L}\p{P}\p{Z}\p{N}\n]{1,})/ui", '', strip_tags($request->input('text')));
             DB::insert('
diff --git a/includes/pages/user_questions.php b/includes/pages/user_questions.php
index e90ea011..e4f35577 100644
--- a/includes/pages/user_questions.php
+++ b/includes/pages/user_questions.php
@@ -61,11 +61,11 @@ function user_questions()
                     return error(_('Incomplete call, missing Question ID.'), true);
                 }
 
-                $question = DB::select(
+                $question = DB::selectOne(
                     'SELECT `UID` FROM `Questions` WHERE `QID`=? LIMIT 1',
                     [$question_id]
                 );
-                if (count($question) > 0 && $question[0]['UID'] == $user['UID']) {
+                if (!empty($question) && $question['UID'] == $user['UID']) {
                     DB::delete(
                         'DELETE FROM `Questions` WHERE `QID`=? LIMIT 1',
                         [$question_id]
diff --git a/includes/sys_auth.php b/includes/sys_auth.php
index f1ec3192..e0ed67e5 100644
--- a/includes/sys_auth.php
+++ b/includes/sys_auth.php
@@ -11,10 +11,9 @@ function load_auth()
 
     $user = null;
     if (isset($_SESSION['uid'])) {
-        $user = DB::select('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$_SESSION['uid']]);
-        if (count($user) > 0) {
+        $user = DB::selectOne('SELECT * FROM `User` WHERE `UID`=? LIMIT 1', [$_SESSION['uid']]);
+        if (!empty($user)) {
             // User ist eingeloggt, Datensatz zur Verfügung stellen und Timestamp updaten
-            $user = array_shift($user);
             DB::update('
                 UPDATE `User`
                 SET `lastLogIn` = ?
diff --git a/src/Database/Db.php b/src/Database/Db.php
index b433f40d..9422ae77 100644
--- a/src/Database/Db.php
+++ b/src/Database/Db.php
@@ -79,6 +79,23 @@ class Db
 
         return self::$stm->fetchAll(PDO::FETCH_ASSOC);
     }
+    
+    /**
+     * Run a select query and return only the first result or null if no result is found.
+     * @param string $query
+     * @param array  $bindings
+     * @return array|null
+     */
+    public static function selectOne($query, array $bindings = [])
+    {
+        $result = self::select($query);
+        
+        if(empty($result)) {
+            return null;
+        }
+        
+        return array_shift($result);
+    }
 
     /**
      * Run an insert query