how to retrieve a table with many tables with PDO - php

Question

Recently I've been using PDO
and I'd like to get a table with hasmany related table.
I can get a table with the tables like this
array (
0 =>
stdClass::__set_state(array(
'order_id' => '170',
'purchase_id' => '222',
'product_option_id' => '014',
)),
1 =>
stdClass::__set_state(array(
'order_id' => '170',
'purchase_id' => '600',
'product_option_id' => '015',
)),
)
with SQL query like this
SELECT ord.order_id,puc.purchase_id,puc.product_option_id
FROM order ord
JOIN purchase puc
ON ord.order_id = puc.order_id
WHERE ord.order_id = '170'
However I'd like to get this data like this
array (
0 =>
array(
'order_id' => '170',
'purchase_id' => '222',
'purchase' => array(
0 =>
array(
'purchase_id' => '222',
'product_option_id' => '014',
),
1 =>
array(
'purchase_id' => '600',
'product_option_id' => '015',
),
)
)
)
How do get the data like this with PDO?
Thank you

Answer 1

Luckily, you CAN have it with PDO.
Were you need anything but id from orders, the mission were impossible.
But as long as you need only unique value from orders, you can get the thing like this
array (
170 =>
array(
0 =>
array(
'purchase_id' => '222',
'product_option_id' => '014',
),
1 =>
array(
'purchase_id' => '600',
'product_option_id' => '015',
),
)
)
)
with as simple code as
$sql = "your sql";
$pdo->query($sql)->fetchAll(PDO::FETCH_GROUP);
However, I see very little sense in fetching the same order ID usedto filter the data. May be it should be some other query that is closer to your real needs? Like one that is fetching several orders?

Answer 2

You can't get it like this with PDO, but you can rearrange the results. A possible way to do it would be to use the array_reduce function.
$orders = array_reduce($results, function ($carry, $item) {
if (!isset($carry[$item->order_id])) {
$carry[$item->order_id] = array(
'order_id' => $item->order_id,
'purchase' => array(array(
'purchase_id' => $item->purchase_id,
'product_option_id' => $item->product_option_id,
));
);
} else {
$carry[$item->order_id]['purchase'][] = array(
'purchase_id' => $item->purchase_id,
'product_option_id' => $item->product_option_id,
);
}
return $carry;
}, array());