PHP PDO fetchAll then json_encode doesn't work

Question

I have a strange issue. I have a simple PHP script that uses PDO to get all countries from a database then returns the result as json. When I use the fetch function instead of fetchAll everything works as expected. When I print_r the data is there.

Doesn't work:

 $sql = "SELECT * FROM countries";
if($stmt = $_db->prepare($sql))
{
    $stmt->execute();
    $data = $stmt->fetchAll(PDO::FETCH_ASSOC);
    $stmt->closeCursor();

    header("content-type:application/json");

    echo json_encode($data);
    exit();

}

Works:

 $sql = "SELECT * FROM countries";
if($stmt = $_db->prepare($sql))
{
    $stmt->execute();
    $data = $stmt->fetch(PDO::FETCH_ASSOC);
    $stmt->closeCursor();

    header("content-type:application/json");

    echo json_encode($data);
    exit();

}

Results of print_r:

Array
(
[0] => Array
    (
        [id] => 1
        [name] => Afghanistan
    )

[1] => Array
    (
        [id] => 2
        [name] => Åland Islands
    )

[2] => Array
    (
        [id] => 3
        [name] => Albania
    )
....
[248] => Array
    (
        [id] => 249
        [name] => Zimbabwe
    )

)
1

Answer 1

try

$dbh = new PDO("mysql:host=$dbhost;dbname=$dbname", $dbuser, $dbpass, array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));

With:

array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8")

Answer 2

When you have a problem with JSON , there is a function json_error() .

After learning that there is a problem with encoding, tell your database to return data in utf8 :

$_db->query("SET NAMES utf8");
$data = $_db->query("SELECT * FROM countries")->fetchAll(PDO::FETCH_ASSOC);

header("content-type:application/json");
echo json_encode($data);
exit();

Answer 3

Try to setup the charset at PDO initialization like this

$_db = new PDO("mysql:host=$host;dbname=$dbname;charset=UTF8;", $dbuser, $dbpass);

Note the end of the first parameter above charset=UTF8;

Answer 4

fetchall documentation says retrieves an array of all fetch data simutaneously. In this case, It seems your fetchall function assigned result array into arraylist.

Here is the reference link below,

PDO fetch / fetchAll