Nested While Loop not working - php

Question

I am developing a webservice for and android app the webservice is in PHP fetching data from a MySQL database ... The problem that I am having is that some of the projects have multiple details but my code is only fetching one detail for every project. I am getting the data in JSON format.
You can check this Here
Here is my code
function requiredData(){
$db = $this->dbConnection();
//$sql = "SELECT * FROM projects JOIN project_details ON projects.project_id=project_details.project_id";
$sql = "SELECT * FROM projects";
$queryResult = $db->query($sql);
if($queryResult->num_rows > 0){
while($row = $queryResult->fetch_assoc()){
$pid = $row['project_id'];
$detailsql = "SELECT * FROM project_details WHERE project_id=$pid";
$sqlResult = $db->query($detailsql);
if($sqlResult->num_rows > 0){
while ($d = $sqlResult->fetch_assoc()){
$r = array(
"project_id" => $d['project_id'],
"project_detail" => array(
"work_done" => $d['project_detail'],
"payment_for_work" => $d['project_payment'],
"payment_status" => $d['project_payment_status'],
"detail_id" => $d['project_detail_id']
)
);
}
}
$results[$row['project_name']] = array(
"project_id" => $row["project_id"],
"project_start_date" => $row["project_start_date"],
"project_due_date" => $row["project_due_date"],
"project_currency" => $row["project_currency"],
"project_work_details" => $r
);
}
}
return $results;
}
Thanks in advance for your help

Answer 1

The issue is in the second while loop. You are assigning array to $r, and $r value overwrites every time.
So, I am assigning now array to an other array, So it will become 2 dimensional array, like this;
while ($d = $sqlResult->fetch_assoc()){
$r[] = array(
"project_id" => $d['project_id'],
"project_detail" => array(
"work_done" => $d['project_detail'],
"payment_for_work" => $d['project_payment'],
"payment_status" => $d['project_payment_status'],
"detail_id" => $d['project_detail_id']
)
);
}
Now you can use $r, it will have multiple details of the project.