如何在PHP中以json格式转换mysql查询的结果？

Question

i want to convert the result of mysql query into format json

The query return a lot fo records but the print_r of json doesn't return anything

$sql="select concat(sig,doc)as Order,date,age from ordertable";
$res = $conn->query($sql);
while($row = $res->fetch_assoc()) 
    {
        $rows[] = $row;
    }

$json = json_decode($rows, true);
fwrite($handle, "json: ".print_r($json,true)." \n\n");

Answer 1

You need to change this below two lines as follows,

$json = json_encode($rows); // to convert it into json internal array
//$json = json_encode($rows,JSON_FORCE_OBJECT); // to convert it json object
fwrite($handle, "json: $json \n\n");

This should do the trick.