Executing queries with query method in PHP - Mini Project: Build & Apply

Executing queries with query method

📖 Scenario: You are building a simple PHP script to fetch user data from a database. You will practice running SQL queries using the query method.

🎯 Goal: Create a PHP script that connects to a database, runs a SELECT query using the query method, and displays the user names.

📋 What You'll Learn

Create a mysqli connection object named $conn with host 'localhost', user 'root', password '', and database 'testdb'.

Create a SQL query string $sql to select all columns from the users table.

Use the query method on $conn with $sql to get the result in $result.

Loop through $result using fetch_assoc() and print each user's name.

Close the database connection at the end.

💡 Why This Matters

🌍 Real World

Fetching data from a database is a common task in web development to show dynamic content like user profiles or product lists.

💼 Career

Understanding how to execute queries and handle results is essential for backend developers working with PHP and MySQL databases.

1

Create the database connection

Create a mysqli connection object called $conn using new mysqli("localhost", "root", "", "testdb").

PHP

<?php
// Create the mysqli connection object $conn
// Your code here

Need a hint?

Use the new mysqli(host, user, password, database) syntax to connect.

2

Write the SQL query string

Create a string variable called $sql and set it to "SELECT * FROM users".

PHP

<?php
$conn = new mysqli("localhost", "root", "", "testdb");
// Create the SQL query string $sql
// Your code here

Need a hint?

Assign the exact string "SELECT * FROM users" to $sql.

3

Run the query using the query method

Use the query method on $conn with $sql and store the result in $result.

PHP

<?php
$conn = new mysqli("localhost", "root", "", "testdb");
$sql = "SELECT * FROM users";
// Run the query and store the result in $result
// Your code here

Need a hint?

Use $conn->query($sql) to run the query.

4

Fetch and display user names

Use a while loop with $row = $result->fetch_assoc() to print each user's name with echo $row['name'] . "\n";. Then close the connection with $conn->close();.

PHP

query($sql);
// Loop through $result and print each user's name
// Close the connection
// Your code here

Need a hint?

Use fetch_assoc() inside a while loop to get each row as an associative array.