Question

<?php
$link = mysql_connect('localhost', 'user', 'password');
if (!$link) {
die('Failed to connect to MySQL: ' . mysql_error());
}
$db_selected = mysql_select_db('mysql', $link);
if (!$db_selected) {
  die ("Can\'t use db : " . mysql_error());
}
$query = sprintf("SELECT church_id FROM hours 
         WHERE day_of_week = DATE_FORMAT(NOW(), '%w') AND 
         CURTIME() BETWEEN open_time AND close_time",
    mysql_real_escape_string($day_of_week),
    mysql_real_escape_string($open_time),
    mysql_real_escape_string($close_time));
$result = mysql_query($query);

if (!$result) {
    $message = 'Invalid query: ' .mysql_error() . "\n";
    $message .= 'Whole query: ' .$query;
    die($message);
}

while ($row = mysql_fetch_array($result)) {
    echo $row['shop_id'];
}

mysql_free_result($result);
echo "end";
?>

我知道SQL查询通过复制/粘贴到phpmyadmin来工作。我希望脚本只输出shop_id或shop_id系列。现在它输出资源ID＃3。我查找了如何修复它，mysql_fetch_array应该是答案。我做错了什么？

Answer 1

我正在查看您的查询，我只看到您选择了church_id并且您想要输出shop_id，您应该在您的选择中包含这样：

$query = sprintf("SELECT church_id, shop_id FROM hours WHERE day_of_week = DATE_FORMAT(NOW(), '%w') AND CURTIME() BETWEEN open_time AND close_time",
    mysql_real_escape_string($day_of_week),
    mysql_real_escape_string($open_time),
    mysql_real_escape_string($close_time));
$result = mysql_query($query);

Answer 2

这里有几个问题，第一个问题是您正在使用 mysql 扩展，该扩展未维护并正式弃用（由于被删除）。我建议你试试 mysqli ...

$link = new mysqli('localhost', 'user', 'password', 'mysql');
if ($link->errno) {
    throw new Exception($link->error, $link->errno);
}

虽然您已经完成了保护查询的值得称赞的工作，但您确实应该使用 mysqli 中提供的更好的工具，尤其是prepared statements ...

$stmt = $link->prepare('SELECT church_id FROM hours 
     WHERE day_of_week = DATE_FORMAT(NOW(), ?) AND 
     CURTIME() BETWEEN open_time AND close_time');
if (!$stmt) {
    throw new Exception($link->error, $link->errno);
}
$stmt->bindParam('s', $day_of_week); // assuming $day_of_week is properly defined
if (!$stmt->execute()) {
    throw new Exception($stmt->error, $stmt->errno);
}

从 mysqli 预处理语句中获取数据与旧mysql_fetch_array略有不同但是并不困难。一种方法是使用结果绑定

$stmt->bind_result($church_id);
while ($stmt->fetch()) {
    echo $church_id;
}

PHP语法错了吗？输出资源ID＃3

2 个答案: