double data on mysql - php

Question

I use the php operator && to select multiple data so that there is no duplication on mysql.
Does the code that I use below run fine? Is there a more simple use of PHP operators?
$date= date('Y/m/d');
$cekcount = mysql_num_rows(mysql_query("SELECT * FROM `pending_media` where `mediaid`='$dielz'"));
$cekcount2 = mysql_num_rows(mysql_query("SELECT * FROM `media` where `mediaid`='$dielz'"));
$selectcount = mysql_query("SELECT * FROM `media` where `date`='$date' AND `uplink`='$nam'");
$cekcount3 = mysql_num_rows($selectcount);
if($cekcount == 0 && $cekcount2 == 0 && $cekcount3 == 0){
mysql_query("INSERT INTO pending_media VALUES('','$nam','$dielz')");

Answer 1

Upgrade to mysqli, I'll recommend object-oriented syntax because it is nicer to work with.
In accordance with the best practice of "minimize calls to the database", I'll condense your three queries into a single, united SELECT call then check for a non-0 result.
My untested suggestion using mysqli's object-oriented syntax (I did test the SELECT query in PHPMyAdmin):
$query = "SELECT SUM(tally)
FROM (
SELECT COUNT(*) AS tally
FROM pending_media
WHERE mediaid = ?
UNION ALL
SELECT COUNT(*)
FROM media
WHERE mediaid = ? OR (date = ? AND uplink = ?)
) t";
$conn = new mysqli("localhost", "root","","dbname");
$stmt = $conn->prepare($query);
$stmt->bind_param("ssss", $dielz, $dielz, $date, $nam);
$stmt->execute();
$stmt->bind_result($tally);
$stmt->fetch();
if (!$tally) {
$stmt->close();
// insert qualifying data
$stmt = $conn->prepare("INSERT INTO pending_media VALUES ('',?,?)");
$stmt->bind_param("ss", $nam, $dielz);
if ($stmt->execute()) {
echo "Insert Query Error"; // $stmt->error;
}else{
echo "Success";
}
}