Direct database queries (wpdb) in Wordpress - Mini Project: Build & Apply

Direct Database Queries with wpdb in WordPress

📖 Scenario: You are building a WordPress plugin that needs to fetch and display user information directly from the WordPress database using the wpdb class.This is useful when you want to run custom queries beyond the standard WordPress functions.

🎯 Goal: Learn how to safely run direct database queries using wpdb to get user data and display it.

📋 What You'll Learn

Use the global $wpdb object to access the database

Write a query to select user data from the $wpdb->users table

Use a variable to set a minimum user ID threshold

Fetch the results as an array of objects

Display the user login names in a loop

💡 Why This Matters

🌍 Real World

Direct database queries with wpdb are useful when you need custom data retrieval beyond WordPress built-in functions, such as custom reports or plugin features.

💼 Career

Knowing how to safely query the WordPress database directly is a valuable skill for WordPress developers building custom plugins or themes.

1

Set up the global wpdb object and write the base query

Write the line to declare the global $wpdb variable and create a string variable called $query with the value "SELECT * FROM $wpdb->users".

Wordpress

# Declare global $wpdb and create base query string
# Your code here

Need a hint?

Remember to use global $wpdb; to access the database object inside your function or file.

2

Add a variable to filter users by minimum ID

Create a variable called $min_user_id and set it to 5. Then update the $query string to select users with ID greater than or equal to $min_user_id using a WHERE clause.

Wordpress

users}";

// Add minimum user ID filter
# Your code here

Need a hint?

Use a WHERE clause in your SQL query to filter by ID.

3

Run the query and get results as objects

Use the $wpdb->get_results() method with the $query variable to fetch the results. Store the results in a variable called $users.

Wordpress

users} WHERE ID >= $min_user_id";

// Fetch users from database
# Your code here

Need a hint?

Use $wpdb->get_results() to get an array of objects from your SQL query.

4

Loop through results and display user login names

Write a foreach loop to go through the $users array. Inside the loop, echo the user_login property of each user object inside a paragraph tag.

Wordpress

users} WHERE ID >= $min_user_id";
// Fetch users from database
$users = $wpdb->get_results($query);

// Loop and display user login names
# Your code here

Need a hint?

Use foreach to loop through the array and access each user's user_login property.