Help with multiple queries

The second query works fine by itself, so why doesn't it work when the first query is in front of it and the else is triggered?
still spits out the print with no errors.

[PHP]
<? include("dbconnect.php");
$result = mysql_query("SELECT CTRL_NUM "
. "FROM inventory "
."WHERE CTRL_NUM = $_POST[ctrl_num] ");

$res = mysql_fetch_array($result);

if( $_POST[ctrl_num] = $res[0])
{

print ("Record could not be added."); print ("Item already exists.");

}
else
{
mysql_query ("INSERT INTO inventory (CTRL_NUM, PART_NUM, SHELF_BIN, UNIT_ISSUE, PART_TYPE, WHSE, VENDOR, MANUFACTUR, SYSTEM, DOM, SUB_SYS, validation, Repairstat, QAstat)
VALUES ('$_POST[ctrl_num]', '$_POST[part_num]', '$_POST[shelf_bin]', '$_POST[unit_issue]', '$_POST[part_type]', '$_POST[whse]', '$_POST[vendor]', '$_POST[manufactur]', '$_POST[system]', '$_POST[dom]', '$_POST[sub_sys]', '$_POST[validation]', '$_POST[repairstat]', '$_POST[qastat]')");

print ("Your record has been added.");
}
mysql_close();
?>
[/PHP]

re: Help with multiple queries

the code looks fine
posible problem:
u trying to insert improper values into the table
e.g. char(asci) into integer column

try this after last query

echo mysql_error();

it will display the error - if any occur

hope that help
jx2

re: Help with multiple queries

actually it was simply as the = statement changeing the data to be entered..i wasn't sure if == was useable in php but it seems to be.

re: Help with multiple queries

lol i didnt notice that eighter :-) well done