Retrieve sql data and generate as json file - php

Question

I am trying to retrieve the data from mySQL and generate as JSON file.
But the output is just showing only 1 row.
There are many rows inside the database table.
What is wrong with this code?
$sql = "SELECT * FROM form_element";
$result = mysqli_query($conn, $sql);
$response = array();
$data_array = array();
if (mysqli_num_rows($result) > 0) {
// output data of each row
while($data = mysqli_fetch_assoc($result)) {
$id = $data['id'];
$name = $data['name'];
$email = $data['email'];
$phone = $data['phone'];
$address = $data['address'];
$data_array = array(
'name' => $name,
'email' => $email,
'phone' => $phone,
'address' => $address
);
}
} else {
echo "0 results";
}
$response['data_array'] = $data_array;
$fp = fopen('results.json', 'w');
fwrite($fp, json_encode($response));

Answer 1

You're overwriting $data_array every time in the loop.
So, this part:
$data_array = array(
'name' => $name,
'email' => $email,
'phone' => $phone,
'address' => $address
);
should be changed to:
$data_array[] = array(
'name' => $name,
'email' => $email,
'phone' => $phone,
'address' => $address
);
Then each row is added to the $data_array.