PHP & MySQL · Lesson 2 of 11

Connecting PHP with MySQL

Connect through PDO and report connection failures safely.

Lesson

PDO provides a consistent interface for database connections. Read credentials from protected configuration, enable exception errors, and specify a character set in the DSN. Do not display database exceptions to end users; log details securely and return a generic error response. The example uses MySQL UTF-8 and exception mode; credentials belong in environment configuration. Further guidance Use migrations to version schema changes, constraints to protect relationships, and prepared statements for every dynamic value. Scope writes with a precise condition, check affected rows, and use transactions when multiple statements must succeed together. Store credentials outside source control. Practice task: Create a fresh example for Connecting PHP with MySQL. Predict the result before running it, then change one input and explain why the result changes. Test a normal case and one boundary or invalid case where it applies. Compare your output with the example and note one rule you would use in a real project.

Code examples

PHP

$pdo = new PDO(
    'mysql:host=127.0.0.1;dbname=app;charset=utf8mb4',
    getenv('DB_USERNAME'),
    getenv('DB_PASSWORD'),
    [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]
);

Expected output

A PDO connection or an exception for the application to handle

Key points

Connect through PDO and report connection failures safely.
Use prepared statements for values and constraints for data integrity.
Scope writes carefully and verify their result.

Your learning progress

Finish this lesson

Optional practice

PHP playground

This site does not execute learner-provided PHP code. Connect a secured PHP sandbox service before enabling code execution.

Execution is disabled. No code is sent to a server.