public function replace($table, $arr, $pks){

        $values = '';

        $keys = '';

        $mergeValues = '';

        $upStatement = '';

        $first = true;

        foreach($arr as $key => $val){

            if (!$first){

                $values .= ',';

                $keys .= ',';

                $mergeValues .= ',';

                $upStatement .= ',';

            }

            else{

                $first = false;

            }

            $values .= "'{$val}'";

            $keys .= $key;

            $mergeValues .= "merge.{$key}";

            $upStatement .= "tab.{$key} = merge.{$key}";

        }

        $first = true;

        $pkstr = '';

        foreach($pks as $pk){

            if (!$first){

                $pkstr .= ' AND ';

            }

            else{

                $first = false;

            }

            $pkstr .= "tab.{$pk} = merge.{$pk}";

        }

        $sql = "MERGE INTO {$table} AS tab

        USING (VALUES

        ({$values})

        ) AS merge ({$keys})

        ON {$pkstr}

        WHEN MATCHED THEN

        UPDATE SET {$upStatement}

        WHEN NOT MATCHED THEN

        INSERT ({$keys})

        VALUES ({$mergeValues})";

        $this->db->query($sql);

    }