php - 如何输入 echo 值以完成查询？

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帮助请。我只想完成查询，但不知道如何放置回声值show tables from (echo value which is the database)。

<?php

if (isset($_POST['database'])){

    echo $_POST['database'];

    $qry = "show tables from ";
    $res = mysqli_query($link,$qry);

    while ($row = mysqli_fetch_array($res)){
         echo $row[0]."<br>";
    }
}

最佳答案

您可以使用输入值轻松完成查询，请参见以下代码：

<?php
 if (isset($_POST['database'])){

 echo $_POST['database'];

 $qry = "show tables from " . $_POST['database'];
 $res = mysqli_query($link,$qry);

  while ($row = mysqli_fetch_array($res)){
  echo $row[0]."<br>";
  }
  }

但是如果这个函数是内部函数，可以看看sql injections hack，但是如果您从外部客户端获取数据库名称，则应该使用以下代码来完成查询：

in PDO :

$query = "SELECT * FROM test_table WHERE enabled = 1 AND id = :id";
$stmnt = $db->prepare($query);
$stmnt->execute(array(':id' => $_POST['id']));