check table exists in codeigniter code example

Example: how to name form another table in codeigniter

$this->db->select('customer_company_reviews.* ,users.*');
$this->db->join('users', 'users.id = customer_company_reviews.customer_company_reviews_author');
$this->db->where('customer_company_reviews_company_id', $id);
$this->db->from('customer_company_reviews');
$this->db->order_by('customer_company_reviews_id', 'desc');
$this->db->limit(1);