Deleting Database Records with PDO

Delete selected database rows with a prepared DELETE statement.

The examples focus on the operation itself, including the important distinction: UPDATE changes rows; DELETE removes them.

What It Does

Use the examples below to observe the behavior on a small dataset before extending it to application code.

Before You Start

The examples use PHP 8.2+ features where shown. Database snippets require the corresponding PDO driver, demo tables, and credentials configured outside source code.

Example 1: Basic Use

Authorize the deletion first; WHERE on a unique key limits its scope.

<?php
$pdo = new PDO(
    "mysql:host=" . (getenv("DB_HOST") ?: "127.0.0.1") . ";dbname=" . (getenv("DB_NAME") ?: "demo") . ";charset=utf8mb4",
    getenv("DB_USER") ?: "app",
    getenv("DB_PASSWORD") ?: "",
    [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_EMULATE_PREPARES => false]
);
$recordId = 3;
$stmt = $pdo->prepare("DELETE FROM users WHERE id = :id");
$stmt->execute(["id" => $recordId]);
echo $stmt->rowCount() === 1 ? "deleted" : "not found";

This example is meant for a configured application environment; output depends on the installed extension, external service, or database contents.

Example 2: Checking Behavior

Authorize the deletion first; WHERE on a unique key limits its scope.

<?php
$pdo = new PDO(
    "mysql:host=" . (getenv("DB_HOST") ?: "127.0.0.1") . ";dbname=" . (getenv("DB_NAME") ?: "demo") . ";charset=utf8mb4",
    getenv("DB_USER") ?: "app",
    getenv("DB_PASSWORD") ?: "",
    [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_EMULATE_PREPARES => false]
);
$recordId = 8;
$stmt = $pdo->prepare("DELETE FROM users WHERE id = :id");
$stmt->execute(["id" => $recordId]);
echo $stmt->rowCount() === 1 ? "deleted" : "not found";

This example is meant for a configured application environment; output depends on the installed extension, external service, or database contents.

Example 3: Practical Example

Authorize the deletion first; WHERE on a unique key limits its scope.

<?php
$pdo = new PDO(
    "mysql:host=" . (getenv("DB_HOST") ?: "127.0.0.1") . ";dbname=" . (getenv("DB_NAME") ?: "demo") . ";charset=utf8mb4",
    getenv("DB_USER") ?: "app",
    getenv("DB_PASSWORD") ?: "",
    [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_EMULATE_PREPARES => false]
);
$recordId = 21;
$stmt = $pdo->prepare("DELETE FROM users WHERE id = :id");
$stmt->execute(["id" => $recordId]);
echo $stmt->rowCount() === 1 ? "deleted" : "not found";

This example is meant for a configured application environment; output depends on the installed extension, external service, or database contents.

Important Behavior and Edge Cases

Require explicit WHERE conditions and restrict authorization before executing mutations.

Comparison with Related Approaches

Common Beginner Mistakes

Key Takeaways

• Delete selected database rows with a prepared DELETE statement.
• Require explicit WHERE conditions and restrict authorization before executing mutations.
• UPDATE changes rows; DELETE removes them.

Use Deleting Database Records with PDO when its documented behavior matches the problem. Test the relevant edge cases in your own runtime before deploying it.