QT - PostgreSQL plugin error - c++

Question

I have an app, that should connect to database.
Under linux i've no problems, but under windows - > i've to add to system "Path" place, where QT enviroment is placed (C:/QT/Tools/QTCreator/bin) otherwise it doesn't work and shows errors like below.
id doesn't work if i place exe file on pendrive too
i would like to send this app to my firends, who shouldn't install QT environment and just run this app.
dirs on my pendrive
/
app.exe
plugins (dir)
-qsqlpsql.dll
-sqldrivers (dir)
--qsqlpsql.dll
what should i do? where did i mistake?
pro file:
QT += core gui sql
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = NZP
TEMPLATE = app
SOURCES += main.cpp\
mainwindow.cpp
HEADERS += mainwindow.h
FORMS += mainwindow.ui
win32{
LIBS += -L"C:/Program Files/psqlODBC/0903/bin"
}
RC_FILE += Info.rc
in my main.cpp:
QApplication a(argc, argv);
qDebug()<<QCoreApplication::applicationDirPath();
a.addLibraryPath(QCoreApplication::applicationDirPath());
a.addLibraryPath(QCoreApplication::applicationDirPath()+"/plugins");
qDebug()<<a.libraryPaths();
MainWindow w;
w.show();
return a.exec();
if i run this app under windows, where i installed QT - everythink is correct, but if i move it on pendrive or run under machine without QT framework - i become error:
QSqlDatabase: QPSQL driver not loaded QSqlDatabase: available drivers: QSQLITE QODBC3 QODBC QPSQL QPSQL7
Failed to open database connection. Invalid driver specfied.
i have looked in internet, but by now without sensible solution
help!

Answer 1

Ugh! i found the problem!
1.
you have in your install destination this folder structure:
yourap.exe
-plugins -> folder
--sqldrivers -> folder
and you have to copy from migws/bin not QT/Tools/Creator/bin!
---qsqlpsql.dll
in your app directory you have to copy
libeay32.dll
with you found in:
C:\Program Files\psqlODBC\0903\bin (http://www.postgresql.org/ftp/odbc/versions/msi/ - ii used https://ftp.postgresql.org/pub/odbc/versions/msi/psqlodbc_09_03_0300.zip)
in your app (main.cpp), just add path:
QApplication a(argc, argv);
a.addLibraryPath(QCoreApplication::applicationDirPath()+"/plugins/");
a.addLibraryPath(QCoreApplication::applicationDirPath());