提问人:CGarden 提问时间:11/11/2019 更新时间:11/11/2019 访问量:56
表单输入中的数组 - Select 语句 MySQLi 参数化
Array from Form Input - Select Statement MySQLi Parameterisation
问:
将表单输入中输入的短语转换为数组,以使用 MySQLi 传递到 MySQL select 语句 where 子句中。我拥有的 php 代码实现了这一点,但我无法练习如何参数化查询以防止 sql 注入攻击。我在这个网站上看了一些问题,但我正在努力将其与我的代码联系起来。
if(!empty($_POST['Message']))
{
$searchStr = get_post($con,'Message');
$aKeyword = explode(" ", $searchStr);
$query ="SELECT m.ID, m.MessageText FROM MessageMain m LEFT OUTER JOIN Likes l on m.ID = l.PostID WHERE MessageText LIKE '%" . $aKeyword[0] . "%'";
for($i = 1; $i < count($aKeyword); $i++) {
if(!empty($aKeyword[$i])) {
$query .= " OR MessageText like '%" . $aKeyword[$i] . "%'";
}
}
$query .= " GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc";
$result = $con->query($query);
$rowcount=mysqli_num_rows($result);
答:
2赞
Dharman
11/11/2019
#1
如果你想根据要匹配的关键词数量动态地构建子句,你可以这样做:WHERE
if (!empty($_POST['Message'])) {
$searchStr = get_post($con, 'Message');
$aKeyword = explode(" ", $searchStr);
$whereClauseArr = [];
foreach ($aKeyword as $keyword) {
if ($keyword) {
$whereClauseArr[] = "MessageText LIKE ?";
$whereValues[] = '%'.$keyword.'%';
}
}
$stmt = $con->prepare(
'SELECT m.ID, m.MessageText
FROM MessageMain m
LEFT OUTER JOIN Likes l on m.ID = l.PostID
WHERE '.implode(' OR ', $whereClauseArr).'
GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc'
);
$stmt->bind_param(str_repeat('s', count($whereValues)), ...$whereValues);
$stmt->execute();
$result = $stmt->get_result();
}
尽管在您的情况下,使用正则表达式检查同一列是否符合多个值可能更好。这将使您的查询更简单,也可能更快,具体取决于您拥有的关键字数量。
if (!empty($_POST['Message'])) {
$searchStr = get_post($con, 'Message');
$aKeyword = explode(" ", $searchStr);
$aKeyword = array_filter($aKeyword); // Remove empty values
$stmt = $con->prepare(
'SELECT m.ID, m.MessageText
FROM MessageMain m
LEFT OUTER JOIN Likes l on m.ID = l.PostID
WHERE MessageText REGEXP ?
GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc'
);
$regexString = implode('|', $aKeyword);
$stmt->bind_param('s', $regexString);
$stmt->execute();
$result = $stmt->get_result();
}
评论
1赞
CGarden
11/12/2019
谢谢你的上述内容。您的代码无需修改即可工作:)我学到了一些非常酷和有用的东西。再次感谢。我用了REGEXP的答案,只是想说!
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