为什么此查询不显示任何信息？ [关闭]

I have got a problem in this query never shows info.

Here is the code:

$db = new DB();
$db->connect();
$query2 = $db->query('SELECT pagado FROM pedidos WHERE email='.$_POST["email"].'');
$row2 = $db->fetch_array($query2);
$query3 = 'SELECT instalado FROM pedidos WHERE email='.$_POST["email"].'';
$row3 = $db->fetch_array($query);
if ($row2["email"] == "S"){
    echo "Su pedido se está instalando";
    echo $resultado3;
}elseif ($row3["email"] == "S"){

You fetch pagado from you query and you try to match with email that's wrong

if ($row2["email"] == "S"){

it would be

if ($row2["pagado"] == "S"){

Also change your query to

 <?php
 $db = new DB();
  $db->connect();
  $query2 = $db->query("SELECT pagado FROM pedidos WHERE email='".$_POST['email']."'");
  $row2 = $db->fetch_array($query2);
  $query3 = "SELECT instalado FROM pedidos WHERE email='".$_POST["pagado"]."'";
  $row3 = $db->fetch_array($query3);
if ($row2["pagado"] == "S"){
    echo "Su pedido se está instalando";
echo $resultado3;
}elseif ($row3["instalado"] == "S"){

there is no variable such as $query so

change your

$row3 = $db->fetch_array($query);

to

$row3 = $db->fetch_array($query3);

also you can change your both query and make it into one

$query2 = $db->query('SELECT pagado,instalado FROM pedidos WHERE email='.$_POST["email"].'');

$row2 = $db->fetch_array($query2);