diff --git a/src/AccessCheck.php b/src/AccessCheck.php
index 9d045d8..7e416a4 100644
--- a/src/AccessCheck.php
+++ b/src/AccessCheck.php
@@ -131,7 +131,7 @@ class AccessCheck implements AccessCheckInterface{
    */
   public function isTermAllowedByUserId($tid, $iUid) {
 
-    $query_result = db_query("SELECT uid FROM {permissions_by_term_user} WHERE tid = :tid AND uid = :uid",
+    $query_result = \Drupal::database()->query("SELECT uid FROM {permissions_by_term_user} WHERE tid = :tid AND uid = :uid",
       array(':tid' => $tid, ':uid' => $iUid))->fetchField();
 
     if (!empty($query_result)) {
@@ -147,7 +147,7 @@ class AccessCheck implements AccessCheckInterface{
    * {@inheritdoc}
    */
   public function isTermAllowedByUserRole($tid, $sUserRole) {
-    $query_result = db_query("SELECT rid FROM {permissions_by_term_role} WHERE tid = :tid AND rid IN (:user_roles)",
+    $query_result = \Drupal::database()->query("SELECT rid FROM {permissions_by_term_role} WHERE tid = :tid AND rid IN (:user_roles)",
       array(':tid' => $tid, ':user_roles' => $sUserRole))->fetchField();
 
     if (!empty($query_result)) {
@@ -164,10 +164,10 @@ class AccessCheck implements AccessCheckInterface{
    */
   public function isAnyPermissionSetForTerm($tid) {
 
-    $iUserTableResults = intval(db_query("SELECT COUNT(1) FROM {permissions_by_term_user} WHERE tid = :tid",
+    $iUserTableResults = intval(\Drupal::database()->query("SELECT COUNT(1) FROM {permissions_by_term_user} WHERE tid = :tid",
       array(':tid' => $tid))->fetchField());
 
-    $iRoleTableResults = intval(db_query("SELECT COUNT(1) FROM {permissions_by_term_role} WHERE tid = :tid",
+    $iRoleTableResults = intval(\Drupal::database()->query("SELECT COUNT(1) FROM {permissions_by_term_role} WHERE tid = :tid",
       array(':tid' => $tid))->fetchField());
 
     if ($iUserTableResults > 0 ||