Why Do My mysqli Prepared Statements Fail, and How Can I Properly Bind Parameters?

Using mysqli Prepared Statements

Getting Started with Prepared Statements

You're attempting to utilize prepared statements, but your code is encountering an error. The issue stems from a missing step: binding parameters to the prepared statement.

Binding Parameters

Prepared statements require you to bind parameters before executing. This process associates external variables with the placeholders (?) in the SQL query.

$name = 'one';
$age = 1;

$stmt = $mysqli->prepare("INSERT INTO users (name, age) VALUES (?,?)");

// Bind parameters (typehint: string, integer)
$stmt->bind_param('si', $name, $age);

// Now you can execute
$stmt->execute();

Do I Need mysqli for Prepared Statements?

Yes, mysqli is required for prepared statements.

Complete Example

Connection:

$mysqli = new mysqli("localhost", "root", "root", "test");
if ($mysqli->connect_errno) {
    echo "Connection failed: " . $mysqli->connect_error;
}

Insertion:

$stmt = $mysqli->prepare("INSERT INTO users (name, age) VALUES (?,?)");

// Bind parameters (typehint: string, integer)
$stmt->bind_param('si', $name, $age);

// Insert row
$stmt->execute();

Selection with Error Handling:

$stmt = $mysqli->prepare("SELECT * FROM users WHERE name = ?");
$stmt->bind_param('s', $name);

$stmt->execute();

if ($stmt->errno) {
    echo "Error: " . $stmt->error;
} else {
    $result = $stmt->get_result();
}

// Process result

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