You may have seen that in Tina4, if we require a Database, it is included via the “index.php” located in project root via the :

<?php

require "vendor/autoload.php";

global $DBA;

//MySQL
$DBA = new \Tina4\DataMySQL(
   https://tina4.com/documentation/doku.php?id=playground:playground "localhost:somedatabase",
    DB_USERNAME, DB_PASSWORD,
    "d/m/Y");
    
  echo new \Tina4\Tina4Php();
 

If you experience any trouble connecting to the DB you can try troubleshoot the following:
1. Ensure that you have the Database native app installed on your device
2. Ensure the correct Database type is being used for your project requirements
3. Ensure the Database version is compatible with SQL, IDE and other tools.
4. Ensure you have all the Tina4 prerequisites installed correctly