diff --git a/main/exercice/exercise.class.php b/main/exercice/exercise.class.php
index 4edd6f9876a..ff264a5b5d9 100755
--- a/main/exercice/exercise.class.php
+++ b/main/exercice/exercise.class.php
@@ -790,13 +790,13 @@ public function save($type_e = '')
         if ($id) {
             // we prepare date in the database using the api_get_utc_datetime() function
             if (!empty($this->start_time) && $this->start_time != '0000-00-00 00:00:00') {
-                $start_time = Database::escape_string($this->start_time);
+                $start_time = $this->start_time;
             } else {
                 $start_time = '0000-00-00 00:00:00';
             }
 
             if (!empty($this->end_time) && $this->end_time != '0000-00-00 00:00:00') {
-                $end_time 	= Database::escape_string($this->end_time);
+                $end_time = $this->end_time;
             } else {
                 $end_time = '0000-00-00 00:00:00';
             }
diff --git a/main/inc/lib/course.lib.php b/main/inc/lib/course.lib.php
index 68d3c8098aa..6f9a04752bd 100755
--- a/main/inc/lib/course.lib.php
+++ b/main/inc/lib/course.lib.php
@@ -4368,6 +4368,8 @@ public static function update_course_ranking(
             'session_id' => $session_id,
             'url_id' => $url_id,
             'creation_date' => $now,
+            'total_score' => 0,
+            'users' => 0
         );
 
         $result = Database::select(
diff --git a/main/inc/lib/document.lib.php b/main/inc/lib/document.lib.php
index d4c57417287..1cc253ea868 100755
--- a/main/inc/lib/document.lib.php
+++ b/main/inc/lib/document.lib.php
@@ -4666,7 +4666,7 @@ public static function generateDefaultCertificate($courseData, $fromBaseCourse =
         $fileFullPath = "{$filePath}/{$fileName}.html";
         $fileSize = 0;
         $fileType = 'file';
-        $templateContent = file_get_contents(api_get_path(SYS_CODE_PATH) . 'gradebook/certificate_template/template.html');
+        $templateContent = file_get_contents(api_get_path(SYS_CODE_PATH).'gradebook/certificate_template/template.html');
 
         $search = array('{CSS}', '{IMG_DIR}', '{REL_CODE_PATH}', '{COURSE_DIR}');
         $replace = array($css.$js, $img_dir, $codePath, $default_course_dir);
diff --git a/main/inc/lib/events.lib.php b/main/inc/lib/events.lib.php
index 063f8b0e1c6..ac57c14990d 100644
--- a/main/inc/lib/events.lib.php
+++ b/main/inc/lib/events.lib.php
@@ -174,21 +174,17 @@ public static function event_access_tool($tool, $id_session = 0)
         $pos2 = isset($_SERVER['HTTP_REFERER']) ? strpos(strtolower($_SERVER['HTTP_REFERER']), strtolower(api_get_path(WEB_PATH)."index")) : false;
         // end "what's new" notification
         if ($pos !== false || $pos2 !== false) {
-            $sql = "INSERT INTO ".$TABLETRACK_ACCESS."
-                        (access_user_id,
-                         c_id,
-                         access_tool,
-                         access_date,
-                         access_session_id
-                         )
-                    VALUES
-                        (".$user_id.",".// Don't add ' ' around value, it's already done.
-                        "'".$courseId."' ,
-                        '".$tool."',
-                        '".$reallyNow."',
-                        '".$id_session."')";
-            Database::query($sql);
+            $params = [
+                'access_user_id' => $user_id,
+                'c_id' => $courseId,
+                'access_tool' => $tool,
+                'access_date' => $reallyNow,
+                'access_session_id' => $id_session,
+                'user_ip' => api_get_real_ip()
+            ];
+            Database::insert($TABLETRACK_ACCESS, $params);
         }
+
         // "what's new" notification
         $sql = "UPDATE $TABLETRACK_LASTACCESS
                 SET access_date = '$reallyNow'
diff --git a/main/inc/lib/fileUpload.lib.php b/main/inc/lib/fileUpload.lib.php
index 60eb80110dc..6f9b0ffe55d 100755
--- a/main/inc/lib/fileUpload.lib.php
+++ b/main/inc/lib/fileUpload.lib.php
@@ -1226,7 +1226,6 @@ function add_document(
     $table_document = Database::get_course_table(TABLE_DOCUMENT);
 
     $params = [
-        'id' => '',
         'c_id' => $c_id,
         'path' => $path,
         'filetype' => $filetype,