What are the errors in this code?

MySQL

the code is:

function pppf($var1)

{

// Get PPPF Code Infomation

$sql = "SELECT * FROM pppf_code";

$pppf_query = MySQL_query($sql);

while($pppf = MySQL_fetch_assoc($pppf_query))

{

$y = MySQL_num_rows($pppf_query);

if ($x<=$y)

{

$pppf_i = $pppf['input_text'];

$pppf_o = $pppf['output_text'];

$pppf_input = array($pppf_input.", '$pppf_i'");

$pppf_output = array($pppf_output.", '$pppf_o'");

}

}

echo $pppf_input['0']." | ".$pppf_output['0']."<br>";

$pppf_out = str_replace($pppf_input, $pppf_output, $var1);

echo $pppf_out;

}