在PHP中使用多条SQL语句实现单条结果查询

<?php
// 连接数据库
$servername = "数据库服务器地址";
$username = "数据库用户名";
$password = "数据库密码";
$dbname = "数据库名";

$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 执行多条SQL语句
$sql = "SELECT * FROM table1; SELECT * FROM table2;";
if ($conn->multi_query($sql)) {
    // 获取结果
    do {
        if ($result = $conn->store_result()) {
            // 处理结果
            while ($row = $result->fetch_assoc()) {
                // 处理单条结果
                // ...
            }
            $result->free();
        }
    } while ($conn->more_results() && $conn->next_result());
} else {
    echo "执行失败: " . $conn->error;
}

// 关闭数据库连接
$conn->close();
?>