MySQL Prepared

PHP MySQL Prepared Statements: A Comprehensive Guide

Prepared statements are a powerful tool for increasing the security and efficiency of PHP applications that interact with databases. This guide will cover the basics of prepared statements and how they can benefit your PHP/MySQL applications. （准备好的语句是一个强大的工具，可以提高与数据库交互的PHP应用程序的安全性和效率。本指南将介绍准备好的语句的基础知识，以及它们如何使您的PHP/MySQL应用程序受益。）

What are Prepared Statements? #

What are Prepared Statements? （什么是预先准备好的陈述？）

Prepared statements are a way to interact with a database by sending pre-compiled SQL statements to the database. This allows for increased security and performance, as the database only needs to compile the statement once and can then reuse it multiple times. （Prepared语句是一种通过向数据库发送预编译的SQL语句来与数据库交互的方式。这样可以提高安全性和性能，因为数据库只需要编译语句一次，然后就可以多次重复使用它。）

Advantages of Prepared Statements #

Advantages of Prepared Statements （准备好的报表的优点）

Security: By using prepared statements, you can prevent SQL injection attacks, as the database will only accept pre-compiled statements and ignore any user-supplied input.Performance: As the database only needs to compile the statement once, the performance of your application will be improved, especially if you are executing the same statement multiple times.Flexibility: Prepared statements allow you to use placeholders for variables in your SQL statements, making it easy to reuse the same statement for different data.

How to Use Prepared Statements in PHP/MySQL #

How to Use Prepared Statements in PHP/MySQL （如何在PHP/MySQL中使用Prepared语句）

To use prepared statements in PHP/MySQL, you need to follow these steps:

Connect to the database.Prepare the SQL statement.Bind variables to the placeholders in the prepared statement.Execute the prepared statement.Fetch the result.Close the prepared statement. （连接到数据库。准备SQL语句。将变量绑定到PREPARED语句中的占位符。执行PREPARED语句。获取结果。关闭PREPARED语句。）

Let’s see an example:

<?php

$conn = mysqli_connect("localhost", "username", "password", "database");
if (!$conn) {
   die("Connection failed: " . mysqli_connect_error());
}

$stmt = mysqli_prepare($conn, "INSERT INTO users (name, email) VALUES (?, ?)");
mysqli_stmt_bind_param($stmt, "ss", $name, $email);

$name = "John";
$email = "[email protected]";
mysqli_stmt_execute($stmt);

$name = "Jane";
$email = "[email protected]";
mysqli_stmt_execute($stmt);

mysqli_stmt_close($stmt);
mysqli_close($conn);

In this example, we connect to the database and then prepare an INSERT statement. We then bind two variables to the placeholders in the prepared statement and execute it twice, with different values each time. （在此示例中，我们连接到数据库，然后准备INSERT语句。然后，我们在准备好的语句中将两个变量绑定到占位符，并执行两次，每次都使用不同的值。）

Conclusion #

Conclusion （小结）

Prepared statements are a powerful tool for increasing the security and efficiency of PHP/MySQL applications. By using prepared statements, you can prevent SQL injection attacks, improve performance, and increase flexibility. This guide has shown you the basics of how to use prepared statements in PHP/MySQL. （准备好的语句是提高PHP/MySQL应用程序安全性和效率的强大工具。通过使用预先准备好的语句，可以防止SQL注入攻击、提高性能并提高灵活性。本指南向您展示了如何在PHP/MySQL中使用准备好的语句的基础知识。）