trouble with database connection first try / time - never before connected

[lse123]

Tried installed XAMPP at 3306 apache/ mysql server and also installed from Oracle/MySQL mysql server 8.0 at 33601 and connector C++
where put libmysql.dll from Oracle MySQL server install /? what is thisa mysqlcppconn8-2-vs14.dll from connector? // tried all and maria DB but getting same message well ?

Console
QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7
Failed to connect.
Press <RETURN> to close this window...

code main.cpp console app ---
DatabaseConnection.pro

QT += core sql
#QT -= gui

CONFIG += c++11 console
CONFIG -= app_bundle

# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

// main.cpp

#include <QCoreApplication>
#include <QtSql>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QDebug>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL"); // QMARIADB
    db.setHostName("127.0.0.1");
    db.setPort(33061);  // <<< MysQL Server 8.0 |  XAMPP MySQL 3306 
    db.setDatabaseName("test");
    db.setUserName("root");
    db.setPassword("123456"); //    XAMPP Mysql empty pass  ''

    if (db.open())
    {
        qDebug() << "Connected!";
    }
    else
    {
        qDebug() << "Failed to connect.";
        return 0;
    }


  QString command = "SELECT my_user.username, department.name AS deptname FROM (SELECT * FROM user WHERE status = 0) AS my_user INNER JOIN department ON department.id = my_user.deptID";
    QSqlQuery query(db);
    if (query.exec(command))
    {
        while(query.next())
        {
            QString username = query.value("username").toString();
            QString department = query.value("deptname").toString();

            qDebug() << username << department;
        }
    }

    return a.exec();
}

[arsinte_andrei]

@lse123 said in trouble with database connection first try / time - never before connected:

Console
QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7
Failed to connect.
Press <RETURN> to close this window...

that means that the Mysql dll is not loaded or is missing - Qt cannot find the library to load MySQL - is just a mater of loading /finding the dll and put it in the right director -sorry I'm a Linux user I do not know on windows but you can google it

https://duckduckgo.com/?q=QSqlDatabase%3A+QMYSQL+driver+not+loaded&t=canonical&atb=v137-1&ia=web

[lse123]

@lse123 said in trouble with database connection first try / time - never before connected:

libmysql.dll from Oracle MySQL server install /? what is thisa mysqlcppconn8-2-vs14.dll

I have to put this
libmysql.dll
or this
mysqlcppconn8-2-vs14.dll
or
libmariadb.dll

in the right directory? 32-bit vs 64-bit driver connector depends only from mysql installation or and from Qt app if 32/64 [for xampp choose 32-bit connector???]???
for connection with XAMPP apache / mysql ???

[lse123]

see and above

what is the correct directory to put the dll??? this C:\Qt\5.12.2\msvc2017\bin\ or in the app build itself... ?

[lse123]

C:\Qt\5.12.2\msvc2017_64\bin\

^^^ put here
started XAMPP

connected !!!!

[arsinte_andrei]

if you solved the problem please mark this topic as solved - in order for others to know that this has been sorted out...

[lse123]

yes SOLVED
how mark this as SOLVED ?????? OK FOUND IT

[lse123]

driver connector -C dll mysql or mariadb
either 32-bit or 64-bit this (the x-bit) must match the y-bit of mysql installation ???

In other words 64-bit MySQL installation REQUIRES 64-bit connector-C++ ... ?

[SGaist]

Hi,

AFAIK, no, but it has to match the architecture of your version of Qt.