PHP MySQL Prepared Statements

Prepared statements in MySQL using PHP are a way to execute a SQL statement multiple times with different parameter values. Prepared statements can help improve performance and prevent SQL injection attacks. Here’s an example of how to use prepared statements in MySQL using PHP:

// MySQL server configuration
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "mydatabase";
// Create a connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check the connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
// Prepare a SQL statement
$stmt = mysqli_prepare($conn, "INSERT INTO users (firstname, lastname, email) VALUES (?, ?, ?)");
// Bind parameters to the statement
mysqli_stmt_bind_param($stmt, "sss", $firstname, $lastname, $email);
// Set parameters and execute the statement
$firstname = "John";
$lastname = "Doe";
$email = "";
$firstname = "Jane";
$lastname = "Doe";
$email = "";
$firstname = "Bob";
$lastname = "Smith";
$email = "";
echo "Data inserted successfully";
// Close the connection

In this example, we first define the configuration for the MySQL server by specifying the server name, username, and password. We also specify the name of the database we want to work with in the $dbname variable. We then create a connection to the server and select the appropriate database using the mysqli_connect() function.

Next, we prepare a SQL statement using the mysqli_prepare() function. The SQL statement contains three placeholders denoted by question marks, which will be replaced with the actual values when the statement is executed.

We then bind parameters to the statement using the mysqli_stmt_bind_param() function. The first argument specifies the statement object, and the second argument specifies the types of the parameters. In this example, we use the “sss” format, which indicates that the parameters are all strings. The remaining arguments specify the actual parameters, which will be replaced for each execution of the statement.

Finally, we set the parameters and execute the statement using the mysqli_stmt_execute() function. We repeat this step for each set of parameters we want to insert into the table.

When using prepared statements, the SQL statement is only compiled once, which can improve performance when executing the statement multiple times with different parameter values. Prepared statements also help prevent SQL injection attacks by separating the SQL code from the parameters.