MySql Deploy App....HELP!!

shathcock

Hello this is my first post but I am in dire need of some help. I have created an application in creator using qt 5.5.1 and visual studio 2013. It connects to a remote MySql Database and when I run it from creator it works fine. When I go to the build release directory and run it it works perfectly.....However When I use windepolyqt (I think that is the name of the tool) and to create an installation folder and I run it the app works fine but I get "driver not loaded driver not loaded" error when I try to connect to the database. I do have the qsqlmysql.dll in the sqldrivers folder. I have been working on this for the last 36 hours and can't figure and I desperately need to deploy this to several machines quickly. Any help would be greatly appreciated!!!!!

hskoglund

Hi, I'm guessing, windeployqt is a fine tool but for database programs it forgets to copy Q5Sql.dll, that could be cause of your problem. When starting windeployqt, try adding the -sql switch, like this:
windeployqt -sql yourapp.exe

shathcock

@hskoglund Thanks for the reply but QT5Sql.dll it did copy QT5Sql.dll into the application directory.

SGaist

Hi and welcome to devnet,

Do you also have the MySQL client libraries deployed with your application ?

hskoglund

Ok. You could try debugging, turn on a trace when Qt loads the plugins.
Before starting your app, set an environment variable to enable the trace:
SET QT_DEBUG_PLUGINS=1

To see the trace output, you can download the DebugView program

shathcock

@SGaist I copied the libmysql.dll file into the application directory to no avail and also tried copying it and the libmysel.lib files to the c:\windows directory.

SGaist

Don't put anything in the windows folder. Next step is what @hskoglund suggested

shathcock

ok the 3 Lines I see that seem to be the ones in the debug

QSalDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers;
QSqlDatabase: an instance of QCoreApplication is required for loading driver plugins

SGaist

The question is going to be silly but: Are you instantiating a QApplication (or Gui or Core) as the first thing in your main function ?

shathcock

Yeah I am just using the normal Windows Application Setup Which has QApplication a (argc, argv); as the first line then just creates an instance of mainwindow.

SGaist

Can you check what QCoreApplication::libraryPaths(); returns ?

shathcock

When I run it from creator it returns the release directory of the release folder that it creates and puts everything into. In other words the directory it puts the .exe file into sorry it's bee a long few days.

hskoglund

Hi, one more thing you could try (since your app runs fine when launched from Qt Creator):
define the environment variable (SET QT_DEBUG_PLUGINS=1) also in Qt Creator (in the Projects Tab, you can set it in Build Environment) then start your app and compare the trace output to the one you got with errors before.

shathcock

Any other Ideas this just really doesn't make any sense. It runs perfectly from the directory that it is compiled to but I can't move it anywhere else and have the MySql drivers working.

hskoglund

Here's another: try skipping using windeployqt; instead switch to using manual deployment, use this nice guide

shathcock

@hskoglund Ok tried it Same Thing!!

hskoglund

Hmmm... The deployment directory/the installation folder your app refuses to run from, is that inside C:\Program Files (x86) or a more normal folder like C:\Qt?

shathcock

No I have it on the Desktop I'll try though!!

shathcock

@shathcock Nope same thing!!!

hskoglund

Hmmmm, if I understand correctly: you have 2 directories/folders with identical contents but in different places on your C: drive. When you doubleciick to launch your app in one of them everything is fine and dandy, but when you try doubleclicking your app in the other directory you get that mysql plugin loading error?