Processing Large Datasets Efficiently with Eloquent `chunk` and `chunkById`

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Product extends Model
{
    // ... model definition ...
}

// Scenario: Process thousands or millions of products

// 1. Using `chunk()`: Iterates over records in chunks
// Best when you don't care about the order or if IDs are not sequential/unique.
Product::chunk(1000, function ($products) {
    foreach ($products as $product) {
        // Process each product in the chunk
        $product->update(['status' => 'processed']);
    }
    // Log::info('Processed a chunk of products.');
});

// 2. Using `chunkById()`: Iterates by ID, more efficient for large datasets
// This method is generally preferred as it's more resilient to changes
// in the underlying data during iteration (e.g., records being added).
Product::where('category_id', 5)
    ->chunkById(500, function ($products) {
        foreach ($products as $product) {
            // Process each product in the chunk
            // For example, trigger a job for each product
            // ProcessProductJob::dispatch($product->id);
            echo "Processing product ID: {$product->id}
";
        }
    }, $column = 'id', $alias = null);

// Example of more complex processing within chunk
Product::chunk(200, function ($products) {
    $productIds = $products->pluck('id')->toArray();
    // Perform a bulk update or other batch operation
    Product::whereIn('id', $productIds)->update(['processed_at' => now()]);
    echo "Updated a chunk of " . count($productIds) . " products.
";
});