Raw expressions in Laravel - Mini Project: Build & Apply

Using Raw Expressions in Laravel Queries

📖 Scenario: You are building a Laravel application that needs to query a database table called products. You want to select products with a price greater than a certain value, but also want to use a raw SQL expression to calculate a discounted price on the fly.

🎯 Goal: Build a Laravel query using raw expressions to calculate a discounted price for products and filter products by price.

📋 What You'll Learn

Create a products array with sample product data

Define a minPrice variable to filter products

Use Laravel's DB::raw() to calculate a discounted price

Write a query that selects product name and discounted price

Filter products where price is greater than minPrice

💡 Why This Matters

🌍 Real World

Raw expressions let you write custom SQL inside Laravel queries, useful for calculations or database-specific functions not directly supported by Laravel's query builder.

💼 Career

Understanding raw expressions is important for backend developers working with Laravel to optimize queries and implement complex database logic efficiently.

1

Create the products data array

Create a PHP array called products with these exact entries: ['name' => 'Laptop', 'price' => 1200], ['name' => 'Phone', 'price' => 800], and ['name' => 'Tablet', 'price' => 600].

Laravel

# Create the products array with exact entries
# Your code here

Need a hint?

Use a PHP array with associative arrays for each product.

2

Define the minimum price filter

Create a variable called minPrice and set it to 700 to filter products with price greater than this value.

Laravel

 'Laptop', 'price' => 1200],
    ['name' => 'Phone', 'price' => 800],
    ['name' => 'Tablet', 'price' => 600],
];

# Define minPrice variable
# Your code here

Need a hint?

Just assign 700 to a variable named minPrice.

3

Write the query with raw discounted price

Write a Laravel query using DB::table('products') that selects name and a raw expression for discounted price as price * 0.9 named discounted_price. Use DB::raw() for the raw expression. Filter products where price is greater than minPrice.

Laravel

 'Laptop', 'price' => 1200],
    ['name' => 'Phone', 'price' => 800],
    ['name' => 'Tablet', 'price' => 600],
];

$minPrice = 700;

# Write the query using DB::table and DB::raw
# Your code here

Need a hint?

Use DB::raw('price * 0.9 as discounted_price') inside select() and filter with where('price', '>', $minPrice).

4

Complete the query by getting results

Complete the query by calling get() on the $query variable to retrieve the filtered products with discounted prices.

Laravel

 'Laptop', 'price' => 1200],
    ['name' => 'Phone', 'price' => 800],
    ['name' => 'Tablet', 'price' => 600],
];

$minPrice = 700;

$query = DB::table('products')
    ->select('name', DB::raw('price * 0.9 as discounted_price'))
    ->where('price', '>', $minPrice);

# Get the results from the query
# Your code here

Need a hint?

Call get() on $query and assign to $results.