Help with Pear DB Query & Fetch

First - I apologize for the cross post (also posted in PHP forum) but I am not sure in which forum this post belongs.

I am not a programmer, but I know enough to figure out how to manipulate pre-existing lines of code, usually. However, the programmer that I was working with recently went AWOL and I at a loss for a solution to a recent site issue I am experiencing.

The code below is taken from a page used to create a module which allows my site users to post reviews about individual lenders (in a database). However, each of my site users (also a database) can only post 1 review about each lender. I need to make it possible for site users to post multiple reviews and comments.

FYI - the rating system is a 5-star system with a cumulative effect.

I can supply more code if necessary, but I am really at a loss here. Any help with making this possible would be GREATLY appreciated.

Thank you in advance...

Alanna

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Here is the code snippet:



if ( !defined( 'PEAR_DIR' ) ) {
include_once ( "./init.php" );
}

require ( 'password_protect.php' );

$sql='SELECT revnum FROM reviews WHERE lendnum='.$_POST[lendnum].' AND adminnum='.$admin[userid];

if ($db->getOne($sql) != '') {
echo 'You have already rated this lender.';
exit();
}


$sql="INSERT INTO reviews (lendnum, adminnum, rating, review, author, authphone1, authphone2) VALUES ('$_POST[lendnum]', '$admin[userid]', '$_POST[R1]', '$_POST[S1]', '$admin[fname] $admin[lname]', '$admin[phone1]', '$admin[phone2]')";
$db->query($sql);

$prevlender=$_POST[lendnum];

header("Location:lenderdetails.php?lender=$prevlender");

?>