"Failed to establish a database connection" error, still alive ... (Feat. Google Sheets, MySQL, JDBC & more !)

i'm still facing this "Failed to establish a database connection" error while i'm trying to connect MySQL database with my Google Sheets file.

For more informations, i use PHP version: 5.6.34. I previously used PHP 8, same problem.

Here we go with the code :

var server = "127.0.0.1";
var port = "3306";
var dbName = "dbName";
var username = 'username';
var password = "password";
var url = 'jdbc:mysql://'  + server + ":" + port + "/" + dbName ;

THEN : ​​

function readData(){
    var connection = Jdbc.getConnection(url, username, password);
    Logger.log(connection);

    var statement = connection.createStatement();
    var results = statement.executeQuery("SELECT * FROM dbName");
    var metaData = results.getMetaData();
    var numberCols = metaData.getColumnCount();
    connection.close();


    var spreadsheet = SpreadsheetApp.getActive();
    var sheet = spreadsheet.getSheetByName("Sheet 1");
    sheet.clearContents();

    var newArray = [];
    for (var col = 0 ; col < numberCols ; col++){
      newArray.push(metaData.getColumnName(col+1));
    }

    sheet.appendRow(newArray);
    while(results.next()){
      newArray = [];
      for (var col = 0 ; col < numberCols ; col++){
        newArray.push(results.getString(col+1));
      }
      sheet.appendRow(newArray);
    }
    results.close();
    statement.close();
    sheet.autoResizeColumn(1,numberCols+1);
  }

I've seen many examples on Internet relating the same problems very recently ... Please could you try to solve my problem so that i can continue the achievement of my first Google Apps Script project ?

Thanks in advance.