How do I append MYSQL JSON - php

Question

I have the following in my database when I run SELECT type FROM office;
+--------------------------------------------------------+
| type |
+--------------------------------------------------------+
| a:2:{i:0;s:16:"Shared Workspace";i:1;s:9:"Workshops";} |
+--------------------------------------------------------+
How can I add an extra JSON value for another type of office. Basically I'd like it to add the type "Private Offices". So the value in my DB will then look like:
+-----------------------------------------------------------------------------------+
| type
+-----------------------------------------------------------------------------------+
| a:3:{i:0;s:16:"Shared Workspace";i:1;s:9:"Workshops";i:2;s:15:"Private Offices";} |
+-----------------------------------------------------------------------------------+

Answer 1

That's not JSON format. It looks like the output of PHP's serialize() function.
There's no SQL function to append values to serialized PHP data. You should fetch it into a PHP application, unserialize() it into a PHP array, then add data to the PHP array and update it back into the database.
Something like the following (some details have been omitted, like the WHERE conditions for the specific row you reference).
<?php
$pdo = new PDO(...);
$typeSerialized = $pdo->query("SELECT type FROM office WHERE ...")->fetchColumn();
$typeArray = unserialize($typeSerialized);
$typeArray[] = "Private Offices";
$typeSerialized = serialize($typeArray);
$stmt = $pdo->prepare("UPDATE office SET type = ? WHERE ...");
$stmt->execute([$typeSerialized]);