unable to open MS-Access DB on QT Application

mustafa · 27 Oct 2018, 05:04

i have a simple program in qt and what is this program do is to open\read a microsoft access datebase (.mdb or .accdb) and display the db tables.
however my problem is that i cant even open the db at the first place
i have db located in the c drive (C:\Qt_Project\Database1.accdb)
in the (.pro) file i have included

QT       += core gui sql

included libraries are:

#include <QSqlDatabase>
#include <QDebug>
#include <QSqlError>

my code is:

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC","AccessDB");
db.setDatabaseName("DRIVER={Microsoft Access Driver (*.mdb, *.accdb)};FIL={MS Access};DBQ=C://Qt_Project//Database1.accdb");
if(db.open())
  qDebug() << "oK";
else
  qDebug() << db.lastError().text();

and finally my output is

 "[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified QODBC3: Unable to connect"

i've goggled the web about this problem i'm facing and maybe "not sure" it's because of the registry because i usually use a cleaner to clean my pc which is cleaning registry also

when i use the code

bool ok = QSqlDatabase::isDriverAvailable("QODBC");

it retures

true

that means there is no problems with the driver

please help , thanks u

hskoglund · wrote on 26 Oct 2018, 17:31

Hi, double forward slashes I think confuses Windows, try backward slashes instead:

db.setDatabaseName("DRIVER={Microsoft Access Driver (*.mdb, *.accdb)};FIL={MS Access};DBQ=C:\\Qt_Project\\Database1.accdb");

mustafa · 27 Oct 2018, 08:46

hello @hskoglund i did what you say and this was the output

QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.
"[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified QODBC3: Unable to connect"

hskoglund · wrote on 26 Oct 2018, 22:48

Hmm, try simplifying by skipping the FILxx stuff::

db.setDatabaseName("DRIVER={Microsoft Access Driver (*.mdb, *.accdb)}; DBQ=C:\\Qt_Project\\Database1.accdb");

Also, check that you have MS-Access installed on your computer and that you can open C:\Qt_Project\Database1.accdb from MS-Access.

Andy314 · 27 Oct 2018, 08:30

@mustafa
Please check this:

bool ok=QSqlDatabase::isDriverAvailable("QODBC");
    if(!ok)
    {
        ErrorMsg="No ODBC driver available!";
        return 1;
    }

JonB · wrote on 27 Oct 2018, 08:30

@Andy314

@mustafa wrote in the first post:

when i use the code
bool ok = QSqlDatabase::isDriverAvailable("QODBC");

it retures
true

that means there is no problems with the driver

JonB · wrote on 27 Oct 2018, 08:46

@Mustafa
Apart from trying without the FIL= as @hskoglund has said, is it possible these days you have a 64- vs 32-bit issue with your drivers & Qt & your app? The sort of thing discussed in https://stackoverflow.com/a/25428598/489865 ?

Alternatively, have you read the same question from a year ago and resolution at https://forum.qt.io/topic/81321/qtsql-data-source-name-not-found/4 ?

Just a couple of thoughts, no point asking me further about this!

edwards142 · wrote on 3 Sept 2019, 08:58

This post is deleted!