https://doc.qt.io/qt-5/qsqldatabase.html#lastError

it returns TRUE

I think its right

You think or you know?

"error checks are debugging functions ?" - no.
What does db.open() return? And please do not post some screen-shot, print it out!

print(db.open())

If it returns false then check https://doc.qt.io/qt-5/qsqldatabase.html#lastError

error checks are debugging functions ? I debugged it, but there were no error messages. I don't know if I did it right either. Like I said, I'm a total beginner

I want to display the "Leistungen" table in the "offene Leistungen" field. But nothing happens

when I write in the terminal db.open(), then this happens:

from PySide6.QtWidgets import QApplication,QMainWindow
from PySide6 import QtSql
from QT.frm_main import Ui_frm_main


class Frm_main(QMainWindow, Ui_frm_main):
    def __init__(self):
        super().__init__()
        self.setupUi(self)
        mod_offene_Leistungen = QtSql.QSqlRelationalTableModel()
        mod_offene_Leistungen.setTable("Leistungen")
        mod_offene_Leistungen.select()
        self.tbl_offene_Leistungen.setModel(mod_offene_Leistungen)
        
        


db=QtSql.QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName("Rechnungen.sqlite")
db.open()



app=QApplication()
frm_main=Frm_main()
frm_main.show()
app.exec()

It doesn’t work

What exactly does not work now?
What does db.open() return?

db=QtSql.QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName("Rechnungen.db")
db.open()

It doesn’t work..

sry for the stupid questions

Do you mean the code from the Python documentation of the class ?