DO while based on query result - php

Question

I got a block of the code written in PHP it uses a DB connection to an Oracle DB, i need to run a query on a data and the result for the first query it should be an input of the next query and this should be inside a loop, if i don't got any more result from the next query i should exit the loop, at the moment i am using and integer to loop through max 5 times as i know this the maximum possible results received, but this is dynamic.
My actual code what is working is the following:
this is the form when i input the data
<form name="identificare_cusut" action="test_hlkz.php" method="post">
Scanati piesa: <input type="text" name="piesa"><br>
<input type="submit" value="Cautare">
</form>
php code where i verify data and use function to execute query on DB while i am running a loop.
if (isset($_POST['piesa']) && strlen($_POST['piesa'])>0) {
$barcode = $_POST['piesa'];
}
if (isset($barcode)) {
echo "<tr>";
echo "<th>".$barcode."</th>";
echo "</tr>";
array_push($trasabilitate_array, $barcode);
$x=1;
do {
$arr=get_query_results_hlkz($barcode);
if ($arr) {
foreach ($arr as $row) {
echo "<tr>";
echo "<th>" .$row[0]. "</th>";
echo "</tr>";
$barcode=$row[0];
array_push($trasabilitate_array, $row[0]);
}
}
$x++;
} while ($x <=5);
}
i don't want to use a static solution like while ($x <=5)
Any idea how to fulfill this in a different way?

Answer 1

Should do the trick. So if the next $arr is empty it will exit the loop.
<?php
if (isset($_POST['piesa']) && strlen($_POST['piesa'])>0) {
$barcode = $_POST['piesa'];
}
if (isset($barcode)) {
echo "<tr>";
echo "<th>".$barcode."</th>";
echo "</tr>";
array_push($trasabilitate_array, $barcode);
$x=1;
do {
$arr=get_query_results_hlkz($barcode);
if ($arr != null) {
foreach ($arr as $row) {
if ($arr == null) {
$x = 6;
}
if($x < 6){
echo "<tr>";
echo "<th>" .$row[0]. "</th>";
echo "</tr>";
$barcode=$row[0];
array_push($trasabilitate_array, $row[0]);
}
}
$x++;
}
} while ($x <=5);
}
?>