How to get specific attribute from DB


a:3:{i:0;a:2:{s:21:”wwsd_percent_discount”;s:2:”10″;s:25:”wwsd_minimum_discount_qrt”;s:2:”20″;}i:1;a:2:{s:21:”wwsd_percent_discount”;s:2:”20″;s:25:”wwsd_minimum_discount_qrt”;s:2:”50″;}i:2;a:2:{s:21:”wwsd_percent_discount”;s:2:”30″;s:25:”wwsd_minimum_discount_qrt”;s:3:”100″;}}

I want to get 10, 20, 30 from wwsd_percent_discount.

I wrote this code:

$ getId = $ product->get_id(); global $ wpdb;
$ result = $ wpdb->get_results(“SELECT meta_value FROM $ wpdb->postmeta WHERE post_id=’$ getId’ AND meta_key =’wwsd_wholesale_discount_data'”);

if ( !empty( $ result ) ) {

foreach ( $  result as $  r ) {     echo "<br>".$  r->meta_value; } 

}

Please help

Thanks