PHP PDO::quote() Method: Usage and Examples

Quotes a single string for a database SQL literal when the driver supports it.

The objective is to understand the behavior and operational limits, not only the method name.

What It Does

Quotes a single string for a database SQL literal when the driver supports it.

Syntax and Return Value

PDO::quote(Parameter #0 [ <required> string $string ], Parameter #1 [ <optional> int $type = PDO::PARAM_STR ]): mixed

The return value and exceptional cases depend on the call described here: Quoting is not a substitute for bound parameters and cannot safely construct SQL identifiers.

Example 1: Basic Use

This self-contained SQLite example uses in-memory demo data; it requires the pdo_sqlite driver.

<?php
$pdo = new PDO('sqlite::memory:', null, null, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
$pdo->exec('CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT NOT NULL, price INTEGER NOT NULL, active INTEGER)');
$pdo->exec("INSERT INTO products (id,name,price,active) VALUES (1,'Desk',120,1),(2,'Lamp',35,1),(3,'Chair',85,0)");
$quoted = $pdo->quote('O\'Reilly 1');
echo $quoted; // Prefer bound parameters for real queries.

Example 2: A Second Scenario

This self-contained SQLite example uses in-memory demo data; it requires the pdo_sqlite driver.

<?php
$pdo = new PDO('sqlite::memory:', null, null, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
$pdo->exec('CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT NOT NULL, price INTEGER NOT NULL, active INTEGER)');
$pdo->exec("INSERT INTO products (id,name,price,active) VALUES (1,'Desk',120,1),(2,'Lamp',35,1),(3,'Chair',85,0)");
$quoted = $pdo->quote('O\'Reilly 2');
echo $quoted; // Prefer bound parameters for real queries.

Example 3: Practical Checks

This self-contained SQLite example uses in-memory demo data; it requires the pdo_sqlite driver.

<?php
$pdo = new PDO('sqlite::memory:', null, null, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
$pdo->exec('CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT NOT NULL, price INTEGER NOT NULL, active INTEGER)');
$pdo->exec("INSERT INTO products (id,name,price,active) VALUES (1,'Desk',120,1),(2,'Lamp',35,1),(3,'Chair',85,0)");
$quoted = $pdo->quote('O\'Reilly 3');
echo $quoted; // Prefer bound parameters for real queries.

Important Behavior and Edge Cases

Quoting is not a substitute for bound parameters and cannot safely construct SQL identifiers.

For production use, also account for error handling, data validation, resource limits and environment-specific driver behavior.

Comparison with Related Approaches

Common Beginner Mistakes

Key Takeaways

• Quotes a single string for a database SQL literal when the driver supports it.
• Quoting is not a substitute for bound parameters and cannot safely construct SQL identifiers.
• prepare with bindValue is preferred for SQL values.

Choose this API or pattern when its exact semantics match your task, and verify the result against the database driver and runtime used by your application.