Problem using Mysql driver

harryF

set the environment variable QT_DEBUG_PLUGINS to 1, what kind of output do you get?

evanxg852000

as you said I ahev done that now using this

@#include <QtGui/QApplication>
#include <QtSql>

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

QSqlDatabase::addDatabase("MYSQL");


return a.exec&#40;&#41;;

}
@

I am getting this error now :

Starting C:\Users\Administrator\Desktop\testger-build-desktop\release\testger.exe...
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlite4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlite4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlited4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlited4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlmysql4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlmysql4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlmysqld4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlmysqld4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlodbc4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlodbc4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlodbcd4.a"
"The file 'C:/Qt/2010.04/qt/plugins/sqldrivers/libqsqlodbcd4.a' is not a valid Qt plugin."
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlite4.dll"
keys ("QSQLITE")
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlited4.dll"
"The plugin 'C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlited4.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)"
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlmysql4.dll"
keys ("QMYSQL3", "QMYSQL")
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlmysqld4.dll"
"The plugin 'C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlmysqld4.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)"
not a plugin
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlodbc4.dll"
keys ("QODBC3", "QODBC")
QFactoryLoader::QFactoryLoader() looking at "C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlodbcd4.dll"
"The plugin 'C:/Qt/2010.04/qt/plugins/sqldrivers/qsqlodbcd4.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)"
not a plugin
QSqlDatabase: MYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL3 QMYSQL QODBC3 QODBC

harryF

The driver name for the Qt MySQL driver is "QMYSQL", not "MYSQL".

evanxg852000

change it but the same output

DenisKormalev

Output in your last post is simply a debug and it is ok that it contains all this strings. Is behavior changed or still database is unavailable?

evanxg852000

surprisingly it's come up . thanks a lot but i think they are subtle things going on . thanks very much

red_eye

I too am struggling with the QMYSQL driver issue in building a Windoze application. A first with Qt 4.6 commercial & VS 2008, I follow the plugin instrictions in Assistant, the "driver is not loaded" and the Assistant says it's usually an issue with the build key. Perhaps someone could suggest a solution to this.

In Linux I recompiled the Qt source with Mysql in the configuration or something like that, and life was good. Do I have to do the same in Winblows too?

This shouldn't be so difficult. Come on Qt experts, let go of the little details please.

evanxg852000

I solved mine on a french source. I used qt creator to built on the commande line. but really this drivers gives some unexpected result from time to time . i succed to built and test it, 2 days later i tried to work on my project it wsa not working any more . my source is "Here":http://giminik.developpez.com/articles/C++-Qt4/installation-mysql-firebird-openssl/

its in french but to summarize . you need to install mysql with the header files .

assuming u have Mingw install do this on cammand line

@cd C:\MySQL-5.0\lib\opt
reimp -d libmysql.lib@

note sometimes reimp is not in your mingw bin folder, so u need "Download":ftp://ftp-developpez.com/giminik/C++/Qt4/installation-mysql-firebird-openssl/mingw-utils-0.3.tar.gz

or in mingw utilities folder from sourgeforge.net

after u need to do this @dlltool -k --input-def libmysql.def --dllname libmysql.dll --output-lib libmysql.a@ this process is to make the lib file compatible with mingw implementation.
now u ill need to compile the mysql driver by linking to the lib file that was created in the last process . it is the as in the documentation, but to make u'r life easier i would recomand u to use qt command line tool Mingw . if for some reason u d'ont want there is always a way around. just beaware that compiling with eithercompiler can bring your error. my solution was to clean up everithing and compile again

s.frings

After upgrade to QT 4.7 on windows, I encountered a new problem which I did not have previously: reimp 0.3 and also 0.41 does not work with current version 6.02 of libmysql.dll:

reimp -d libmysql.dll
reimp: libmysql.dll: invalid or corrupt import library

How can I compile the mysql plugin now?

s.frings

My error was that I tried to run reimp on the dll file, but I should use the lib file instead. Oops!