mysql 动态where条件

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 动态 WHERE 条件
$conditions = [];
if (isset($_GET['name'])) {
    $conditions[] = "name = '" . $conn->real_escape_string($_GET['name']) . "'";
}
if (isset($_GET['date'])) {
    $conditions[] = "date = '" . $conn->real_escape_string($_GET['date']) . "'";
}

// 构建 WHERE 子句
$whereClause = "";
if (!empty($conditions)) {
    $whereClause = "WHERE " . implode(" AND ", $conditions);
}

// 执行查询
$sql = "SELECT * FROM myTable " . $whereClause;
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    // 输出数据
    while($row = $result->fetch_assoc()) {
        echo "id: " . $row["id"]. " - Name: " . $row["name"]. " - Date: " . $row["date"]. "<br>";
    }
} else {
    echo "0 结果";
}
$conn->close();
?>