Answers for "transform mysql json in php"

how to receive json data in php

$data = json_decode(file_get_contents('php://input'), true);
print_r($data);
echo $data;

php mysql row to json

$sth = mysqli_query($conn, "SELECT ...");
$rows = array();
while($r = mysqli_fetch_assoc($sth)) {
    $rows[] = $r;
}
print json_encode($rows);