diff --git a/classes/local/dash_framework/query_builder/builder.php b/classes/local/dash_framework/query_builder/builder.php
index 73e86c3..b02def8 100644
--- a/classes/local/dash_framework/query_builder/builder.php
+++ b/classes/local/dash_framework/query_builder/builder.php
@@ -452,13 +452,23 @@ public function query() {
     /**
      * Get number of records this query will return.
      *
+     * @param int $isunique Counted by unique id.
      * @return int
      * @throws dml_exception
      * @throws exception\invalid_operator_exception
      */
-    public function count(): int {
+    public function count($isunique): int {
         $builder = clone $this;
-        $builder->set_selects(['count' => 'COUNT(DISTINCT ' . $this->tablealias . '.id)']);
+
+        if ($isunique) {
+            $builder->set_selects([
+                'uni' => 'CONCAT_WS("-", cm.id, u.id, c.id, cc.id)',
+                'count' => 'COUNT(*)']
+            );
+        } else {
+            $builder->set_selects(['count' => 'COUNT(DISTINCT ' . $this->tablealias . '.id)']);
+        }
+
         $builder->limitfrom(0)->limitnum(0)->remove_orderby();
         if (!$records = $builder->query()) {
             return 0;
diff --git a/classes/local/dash_framework/query_builder/join.php b/classes/local/dash_framework/query_builder/join.php
index 1e23f96..b998534 100644
--- a/classes/local/dash_framework/query_builder/join.php
+++ b/classes/local/dash_framework/query_builder/join.php
@@ -46,6 +46,11 @@ class join {
      */
     const TYPE_LEFT_JOIN = 'LEFT JOIN';
 
+    /**
+     * SQL right Join.
+     */
+    const TYPE_RIGHT_JOIN = 'RIGHT JOIN';
+
     /**
      * @var string Table name of joined table.
      */
diff --git a/classes/local/data_source/abstract_data_source.php b/classes/local/data_source/abstract_data_source.php
index b3ffdab..eb3c216 100644
--- a/classes/local/data_source/abstract_data_source.php
+++ b/classes/local/data_source/abstract_data_source.php
@@ -182,7 +182,7 @@ public function get_paginator(): paginator {
 
         if ($this->paginator == null) {
             $this->paginator = new paginator(function () {
-                $count = $this->get_query()->count();
+                $count = $this->get_query()->count($this->count_by_uniqueid());
                 if ($maxlimit = $this->get_max_limit()) {
                     return $maxlimit < $count ? $maxlimit : $count;
                 }
@@ -719,4 +719,13 @@ public function is_widget() {
         return false;
     }
 
+    /**
+     * Count a data record by uniqueid.
+     *
+     * @return boolean
+     */
+    public function count_by_uniqueid() {
+        return false;
+    }
+
 }