Laravel eager loading use parents column value - php

Question

Here is my scenario, I have 2 table Product and Rack. They have many to many relationship, so there is a pivot table ( History Class ) to connect them .
Tables
This is our Products table:
id
Name
1
Product A
2
Product B
3
Product C
Rack table:
id
code
1
X1
2
Y2
3
Z3
History table:
product_id
rack_id
historyable_id
historyable_type
quantity
Product A
X1
1
Receive
10
Product A
Y1
1
Receive
5
Product A
X1
1
Delivery
2
Product B
X1
2
Receive
10
I want to get list like this:
product_id
rack_id
historyable_id
historyable_type
quantity
Product A
X1
1
Receive
8
Product A
Y1
1
Receive
5
Product B
X1
2
Receive
10
If type receive is 'debit' and delivery is 'credit' to calculate quantity, and i have two unique column in here product_id and rack_id.
Here is my method right now:
public function collection()
{
$products = Product::with('racks')->get();
$results = collect();
foreach ($products as $product) {
foreach ($product->racks as $rack) {
$rackWithHistory = $rack->load(['history' => function ($q) use ($product) {
return $q->where('product_id', $product->id)->with('histories:id');
}]);
$results->push([
'product_name' => $product->name,
'product_description' => $product->description,
'location' => $rack->code,
'quantity' => $rack->getQuantity($rackWithHistory->history)
]);
}
}
return $result;
}
It works but in large data (try in 2000rows) that takes a very long time, and always touch
php - Allowed memory size of 134217728 bytes exhausted can you guys give me some tips so it can load faster?

Answer 1

You could try chunking the data
Product::with('racks')->chunk(100, function ($products) use($results) {
foreach ($products as $product) {
foreach ($product->racks as $rack) {
$rackWithHistory = $rack->load(['history' => function ($q) use ($product) {
return $q->where('product_id', $product->id)->with('histories:id');
}]);
$results->push([
'product_name' => $product->name,
'product_description' => $product->description,
'location' => $rack->code,
'quantity' => $rack->getQuantity($rackWithHistory->history)
]);
}
}
});
When you chunk data, you only take a x amount of items at a time. In your case 100 items at a time.
https://laravel.com/docs/8.x/queries#chunking-results