Executing SELECT query return false - php

Question

I have a PHP site that I uploaded in 000webhost. It needs a database to store data. But when I try to sign in it didn't sign in. When I check the connection it turns out the connection was fine. Still not able to access the database. So I wrote a small script to check database access and it failed. I have a table named songs which contains some songs.
Here is the script :
<?php
ob_start();
session_start();
$host = 'localhost';
$user = 'xxxxxxx';
$pass = 'xxxxxxx';
$db = 'xxxxxxx';
$timezone = date_default_timezone_set("Asia/Kolkata");
$con = new PDO("mysql:host=$host;dbname=$db", $user, $pass);
if($con)
{
echo "Connection success";
$query = mysqli_query($con, "SELECT * FROM songs");
if($query){
$tb = mysqli_fetch_array($query);
print_r($tb);
}
else {
echo " failed db access";
}
}
else {
echo " connection failed";
}
?>
The details have been kept hidden for security reasons.
The above script gives the following output:
Connection success failed db access

Answer 1

It doesn't work, because you're using PDO for connection and mysqli to query. Change your connection to mysqli
$con = new mysqli($servername, $username, $password, $dbname);
or change your query to PDO
$query = $con->query("SELECT * FROM songs");

Answer 2

The output you are showing is misleading, failed db access. As per below code, database was connected successfully and you were executing query, which didn't executed it seems and flow going to else block.
if($query){
// your code
}
else {
echo " failed db access";
}
You need to check,
If you are using same user credentials and has access to the table.
If same table exists
If you have provided correct database details where you have created tables.
==Updated==
As I mentioned earlier, user might not have sufficient privilege to access songs table. To GRANT access, you need to execute following SQL
GRANT ALL PRIVILEGES ON *.* TO '<username>'#'localhost; WITH GRANT OPTION;