insert query to use store the values in wordpress database.
global $wpdb;
$wpdb->insert($table_name,array('author_id' =>$author_id,'author_name' =>$author_name,'author_email'=>$author_email,'created_at'=>current_time('mysql', 1)),array('%d','%s','%s','%s'));
global $wpdb;
$wpdb->insert($table_name,array('author_id' =>$author_id,'author_name' =>$author_name,'author_email'=>$author_email,'created_at'=>current_time('mysql', 1)),array('%d','%s','%s','%s'));