Php mysql Get&Post query to excel - php

Question

I have a page that posts to index page like
index.php?coursecode=COURSECODEHERE
My non-variable query works well. Gives me all table as excel file.
I need to use this query with variables.
<?php
require_once('dbconnect.php');
$setCounter = 0;
$setExcelName = "download_excal_file";
$setSql = "SELECT * FROM courses WHERE coursecode POSTED VARIABLE COURSECODE HERE";
$setRec = mysql_query($setSql);
$setCounter = mysql_num_fields($setRec);
for ($i = 0; $i < $setCounter; $i++) {
$setMainHeader .= mysql_field_name($setRec, $i)."\t";
}
while($rec = mysql_fetch_row($setRec)) {
$rowLine = '';
foreach($rec as $value) {
if(!isset($value) || $value == "") {
$value = "\t";
} else {
//It escape all the special charactor, quotes from the data.
$value = strip_tags(str_replace('"', '""', $value));
$value = '"' . $value . '"' . "\t";
}
$rowLine .= $value;
}
$setData .= trim($rowLine)."\n";
}
$setData = str_replace("\r", "", $setData);
if ($setData == "") {
$setData = "\n no matching records found\n";
}
$setCounter = mysql_num_fields($setRec);
//This Header is used to make data download instead of display the data
header("Content-type: application/octet-stream");
header("Content-Disposition: attachment; filename=".$setExcelName."_Reoprt.xls");
header("Pragma: no-cache");
header("Expires: 0");
//It will print all the Table row as Excel file row with selected column name as header.
echo ucwords($setMainHeader)."\n".$setData."\n";
?>
How can i do that ?

Answer 1

1.- mysql_ is deprecated, switch to PDO or mysqli ASAP
2.- Always sanitize the input, you never know who may call your link and insert stuff (or delete stuff) from your database.
Said that, you can do something like:
$setSql = "SELECT * FROM courses WHERE
coursecode LIKE '".sanitizeThisShit($_GET["coursecode"])."'";