Why won't my WHERE query work? - php

Question

I've been on this for some days now. At first I thought the problem was in binding the parameters but I've simplified back to a basic mysqli page and still can't find the error. I'm passing the key for one of the rows in the search page before this onto this page so that I can show more details of the item which was selected.
I added an echo to test the the isset which prints correctly, also it puts the Key into the URL. If I leave out the WHERE Key = '$Key' it prints out the entire dataset. If I replace $row['Key'] with $Key it prints the whole dataset but with the selected key on every row.
This tells me that it is passing the key correctly and the print function is correct. I've tried using WHERE Key = $_GET['Key'] as well as $Key but neither work. I must be doing something basicly wrong here but after three days of trying every variation on the code I can think of, I have no more ideas.
<?php
$mysqli = new mysqli('localhost','user','password','database');
if ($mysqli->connect_error) {
die('Error : ('. $mysqli->connect_errno .') '. $mysqli->connect_error);
}
if(isset($_GET['Key'])){
$Key = $_GET['Key'];
echo "Got it";
}else{
echo "No input";
}
$results = $mysqli->query("SELECT * FROM engravers WHERE Key ='$Key'");
$img_url = "http://www.xxxxx.net/images/";
print '<table border="1" >';
while($row = $results->fetch_assoc()) {
print '<tr>';
print '<td>'.$row["Key"].'</td>';
print '<td>'.$row["Country"].'</td>';
print '<td>'.$row["Year"].'</td>';
print '<td>'.$row["Description"].'</td>';
print '<td>'.$row["Engraver1Surname"].'</td>';
print '<td>'.$row["Designer1Surname"].'</td>';
print '<td>'.$row["Printer"].'</td>';
print '<td>'.'<img src="'.$img_url.$row['Images'].'" />'.'</td>';
print '</tr>';
}
print '</table>';
$results->free();
$mysqli->close();
?>
</body>

Answer 1

There are many SQL column names you should avoid. Please read: http://technet.microsoft.com/en-us/library/ms189822.aspx
Same Reserved Keywords are in MySQL.
If you use one of those just cover it with ``
$results = $mysqli->query("SELECT * FROM `engravers` WHERE `Key`='$Key'");

Answer 2

In your query you are using column key which is not allowed because this is a reserved keyword.

Answer 3

Man, you're already using mysqli, why are you still interpolating variables in your query? This is the way to pass a string $Key to the parser
$results = $mysqli->prepare("SELECT * FROM engravers WHERE `Key`= ?");
$results->bind_param("s", $Key);
while($row = $results->fetch_assoc()) {
... stuff ...
}
If that doesn't work, I'm sure it's not because the prepared statement is the problem.
PD: key is a reserved word, so please note the fieldname is wrapped in backticks.