How to get specific attribute from DB

Question

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;
    }
}

Answer 1

If the data you placed at the beginning of your question is the result of your database query (I'm unsure by how your question is worded), you will want to take that query result and use the PHP function unserialize() to convert that data to an array, then you can access your data from that array.

Your serialized data will become at array that looks like this:

Array
(
    [0] => Array
        (
            [wwsd_percent_discount] => 10
            [wwsd_minimum_discount_qrt] => 20
        )

    [1] => Array
        (
            [wwsd_percent_discount] => 20
            [wwsd_minimum_discount_qrt] => 50
        )

    [2] => Array
        (
            [wwsd_percent_discount] => 30
            [wwsd_minimum_discount_qrt] => 100
        )
)