$db_connection = pg_connect("host=localhost dbname=xxx user=xxx     password=xxx");
    $result = pg_query($db_connection, "SELECT * FROM taxi_stats.satisfy");
    $data = array();
    while ($row = pg_fetch_array($result))
    {
      $data[] = $row;
    }
    echo json_encode($data);
    pg_close($db_connection);

<script>
d3.json("data.php", function(error, data) {
    if(error){
        console.log(error);
    }
    console.log(data);
});
</script>