Question

我正在尝试检查今天是否有条目，如果没有，则添加一个，如果它已经存在则不然。目前的代码是：

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

$sql .= "SELECT plusamount AS plustotal, minusamount AS minustotal FROM   Juuli WHERE reg_date >= CURRENT_DATE() ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    echo "It already exists!";
} else {
    echo "autowrite should run";
    $sql .= "INSERT INTO Juuli(minusamount) VALUES (0); ";
}
$conn->close();
?>

Answer 1

如果您的SELECT语句按照您希望的方式直接从数据库运行，则以下内容应该有效。（注意用.=替换=）

$sql = "SELECT plusamount AS plustotal, minusamount AS minustotal FROM Juuli WHERE reg_date >= CURRENT_DATE() ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    echo "It already exists!";
} else {
    echo "autowrite should run";
    $sql2 = "INSERT INTO Juuli (minusamount) VALUES (0)";
    $result2 = $conn->query($sql2);
}
$conn->close();

选择然后使用PHP将数据插入MySQL

1 个答案: