<?php
const HOST = 'localhost';
const USER = 'abh';
const PASS = '123';
const DB = 'abc';

try
{
  $conn = new PDO("mysql:host = ".HOST.";dbname = ".DB."", USER, PASS);
  if($conn)
  {
    echo "success";
  }
  else
  {
    echo "error";
  }
  $query  = "select uid from users";
  $result = $conn->query($query);
  if(!$result)
  {
    print_r($conn->errorInfo());
  }
  else
  {
    foreach($result as $row)
    {
      echo $row['uid'];
    }
  }
  //$conn = null;
}
catch(PDOException $e)
{
  echo $e->getMessage();
}
                                                                                                                                                     1,5
?>

//i am getting following error

/*successArray
(
    [0] => 3D000
    [1] => 1046
    [2] => No database selected
)
*/ //please tell me how to fix it