How to build Oracle driver - Windows with MinGW-ERROR

SGaist

Hi,

To add to @raven-worx, you are using a MinGW version of Qt while you are pointing to a MSVC build in your instant client_10_2 SDK.

That won't work, you can't mix and match compilers like that on Windows when using C++ libraries.

jacekkozik

Thank you for the quick reply.
Raven-worx, My mistake, but I corrected makefile and is still a problem.
SGaist you're right, but I've always used the version of MinGW. In Qt msvc I have error. When I compile, I get this message:

In Polish

Błąd budowania / instalowania projektu nienazwany (zestaw narzędzi: Desktop Qt 5.7.1 MSVC2015 32bit)
Podczas wykonywania kroku "qmake"

English translation:

Error building / installing project unnamed (Toolkit: Qt 5.7.1 Desktop MSVC2015 32bit)
When performing step "qmake"

Do I need to install Microsoft Visual Studio Community 2015 and configure it on the QT?

SGaist

If you want to use the MSVC version of the driver then yes, you have to install the VS2015 C++ compiler, You don't need to install the whole Visual Studio stuff, they have now a separate package for the build tools.

Note that you should also check which version of VS was used to build the Oracle driver, you must ensure all matches. Microsoft VS compilers are not compatible one with the other.

jacekkozik

It worked, QT compiles and runs applications :)
But after running nmake:

C:\Qt\Qt5.7.1\5.7\Src\qtbase\src\plugins\sqldrivers\oci>nmake

Microsoft (R) Program Maintenance Utility Version 14.00.24210.0
Copyright (C) Microsoft Corporation.  All rights reserved.

        "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\nmake.exe" -f Makefile.Release all

Microsoft (R) Program Maintenance Utility Version 14.00.24210.0
Copyright (C) Microsoft Corporation.  All rights reserved.

        rc -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_W
INDLL -fo .obj\release\qsqloci_resource.res qsqloci_resource.rc
Microsoft (R) Windows (R) Resource Compiler Version 6.3.9600.17336
Copyright (C) Microsoft Corporation.  All rights reserved.

qsqloci_resource.rc(4) : fatal error RC1015: cannot open include file 'windows.h'.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\rc.EXE"' : return code '0x1'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\nmake.exe"' : return code '0x2'
Stop.

windosw.h is in C:\Program Files (x86)\Windows Kits\8.1\Include\um, I added in Makefile.Debug and Makefile.Release to INCPATH C:\Program Files (x86)\Windows Kits\8.1\Include and has not changed.

SGaist

How did you setup your command line ?

jacekkozik

set INCLUDE=%INCLUDE%;C:\app\instantclient_10_2\sdk\include
set LIB=%LIB%;C:\app\instantclient_10_2\sdk\lib\msvc
cd %QTDIR%\src\plugins\sqldrivers\oci
qmake oci.pro
nmake

Let You See, I write like this.
Thanks for your help:-)

SGaist

From a standard command line or from a VS command line ?

jacekkozik

I tried from VS. Is OK!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Now, I have:

2017-01-16  23:53            75˙776 qsqloci.dll
2017-01-16  23:53               828 qsqloci.exp
2017-01-16  23:53             1˙998 qsqloci.lib
2017-01-16  23:53           164˙352 qsqlocid.dll
2017-01-16  23:53               831 qsqlocid.exp
2017-01-16  23:53         1˙041˙428 qsqlocid.ilk
2017-01-16  23:53             2˙014 qsqlocid.lib
2017-01-16  23:53         1˙716˙224 qsqlocid.pdb

Now, I should copy them to:
C: \ Qt \ Qt5.7.1 \ 5.7 \ msvc2015 \ plugins \ sqldrivers

But how do I get oci.dll, which is the best and correct?

SGaist

Did you re-run qmake before building from that VS cmd line ?

jacekkozik

It is Everything I do:

C:\Program Files (x86)\Microsoft Visual C++ Build Tools>set INCLUDE=%INCLUDE%;c:\app\instantclient_12_1\sdk\include

C:\Program Files (x86)\Microsoft Visual C++ Build Tools>set LIB=%LIB%;c:

C:\Program Files (x86)\Microsoft Visual C++ Build Tools>set LIB=%LIB%;c:\app\instantclient_12_1\sdk\lib\msvc

C:\Program Files (x86)\Microsoft Visual C++ Build Tools>cd c:\Qt\Qt5.7.1_msvc2015\5.7\Src\qtbase\src\plugins\sqldrivers\oci

c:\Qt\Qt5.7.1_msvc2015\5.7\Src\qtbase\src\plugins\sqldrivers\oci>c:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\bin\qmake.exe oci.pro

c:\Qt\Qt5.7.1_msvc2015\5.7\Src\qtbase\src\plugins\sqldrivers\oci>nmake

Microsoft (R) Program Maintenance Utility Version 14.00.24210.0
Copyright (C) Microsoft Corporation.  All rights reserved.

        "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\nmake.exe" -f Makefile.Release all

Microsoft (R) Program Maintenance Utility Version 14.00.24210.0
Copyright (C) Microsoft Corporation.  All rights reserved.

        C:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\bin\moc.exe -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -D_MSC_VER=1900 -D_WIN32 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/mkspecs/win32-msvc2015 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/src/plugins/sqldrivers/oci -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1/QtCore -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore main.cpp -o .moc\release\main.moc
        C:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\bin\moc.exe -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -D_MSC_VER=1900 -D_WIN32 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/mkspecs/win32-msvc2015 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/src/plugins/sqldrivers/oci -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1/QtCore -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore ..\..\..\sql\drivers\oci\qsql_oci_p.h -o .moc\release\moc_qsql_oci_p.cpp
        rc -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -fo .obj\release\qsqloci_resource.res qsqloci_resource.rc
Microsoft (R) Windows (R) Resource Compiler Version 6.3.9600.17336
Copyright (C) Microsoft Corporation.  All rights reserved.

        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -O2 -MD -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\release -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\release\ @C:\Users\jkozik\AppData\Local\Temp\nmC868.tmp
main.cpp
        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -O2 -MD -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\release -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\release\ @C:\Users\jkozik\AppData\Local\Temp\nmCA6D.tmp
qsql_oci.cpp
        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -O2 -MD -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_NO_DEBUG -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -DNDEBUG -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\release -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\release\ @C:\Users\jkozik\AppData\Local\Temp\nmCE56.tmp
moc_qsql_oci_p.cpp
        link /NOLOGO /DYNAMICBASE /NXCOMPAT /INCREMENTAL:NO /DLL /SUBSYSTEM:WINDOWS /VERSION:5.7 /OUT:..\..\..\..\plugins\sqldrivers\qsqloci.dll @C:\Users\jkozik\AppData\Local\Temp\nmD02B.tmp
   Creating library ..\..\..\..\plugins\sqldrivers\qsqloci.lib and object ..\..\..\..\plugins\sqldrivers\qsqloci.exp
        "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\nmake.exe" -f Makefile.Debug all

Microsoft (R) Program Maintenance Utility Version 14.00.24210.0
Copyright (C) Microsoft Corporation.  All rights reserved.

        C:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\bin\moc.exe -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -D_MSC_VER=1900 -D_WIN32 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/mkspecs/win32-msvc2015 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/src/plugins/sqldrivers/oci -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1/QtCore -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore main.cpp -o .moc\debug\main.moc
        C:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\bin\moc.exe -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -D_MSC_VER=1900 -D_WIN32 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/mkspecs/win32-msvc2015 -IC:/Qt/Qt5.7.1_msvc2015/5.7/Src/qtbase/src/plugins/sqldrivers/oci -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql/5.7.1/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1 -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore/5.7.1/QtCore -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtSql -IC:/Qt/Qt5.7.1_msvc2015/5.7/msvc2015/include/QtCore ..\..\..\sql\drivers\oci\qsql_oci_p.h -o .moc\debug\moc_qsql_oci_p.cpp
        rc -D_DEBUG -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -fo .obj\debug\qsqlocid_resource.res qsqlocid_resource.rc
Microsoft (R) Windows (R) Resource Compiler Version 6.3.9600.17336
Copyright (C) Microsoft Corporation.  All rights reserved.

        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -Zi -MDd -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 /Fd.obj\debug\qsqlocid.vc.pdb -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\debug -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\debug\ @C:\Users\jkozik\AppData\Local\Temp\nmD1BF.tmp
main.cpp
        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -Zi -MDd -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 /Fd.obj\debug\qsqlocid.vc.pdb -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\debug -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\debug\ @C:\Users\jkozik\AppData\Local\Temp\nmD47F.tmp
qsql_oci.cpp
        cl -c -nologo -Zc:wchar_t -FS -Zc:strictStrings -Zc:throwingNew -Zi -MDd -D_HAS_EXCEPTIONS=0 -GR -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 /Fd.obj\debug\qsqlocid.vc.pdb -DUNICODE -DWIN32 -DQT_NO_CAST_TO_ASCII -DQT_NO_CAST_FROM_ASCII -DQT_NO_EXCEPTIONS -DQT_PLUGIN -DQT_SQL_LIB -DQT_CORE_LIB -D_WINDLL -I. -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql\5.7.1\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1 -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore\5.7.1\QtCore -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtSql -IC:\Qt\Qt5.7.1_msvc2015\5.7\msvc2015\include\QtCore -I.moc\debug -IC:/utils/my_sql/my_sql/include -IC:/utils/postgresql/pgsql/include -I..\..\..\..\mkspecs\win32-msvc2015 -Fo.obj\debug\ @C:\Users\jkozik\AppData\Local\Temp\nmD8B6.tmp
moc_qsql_oci_p.cpp
        link /NOLOGO /DYNAMICBASE /NXCOMPAT /DEBUG /DLL /SUBSYSTEM:WINDOWS /VERSION:5.7 /OUT:..\..\..\..\plugins\sqldrivers\qsqlocid.dll @C:\Users\jkozik\AppData\Local\Temp\nmDB47.tmp
   Creating library ..\..\..\..\plugins\sqldrivers\qsqlocid.lib and object ..\..\..\..\plugins\sqldrivers\qsqlocid.exp

c:\Qt\Qt5.7.1_msvc2015\5.7\Src\qtbase\src\plugins\sqldrivers\oci>

But I don't know where is oci.dll

SGaist

Looks like the build is successful, no ?

jacekkozik

Yes, so I'm happy.
But I copied dll files and displays the message:

QSqlDatabase: QOCI driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QOCI QOCI8 QODBC QODBC3 QPSQL QPSQL7

Libraries are loaded, because in the message is:
QOCI QOCI8
I think there is a problem with oci.dll, I do not know where I can find this file.

SGaist

You should also take a look at the error returned by QSqlDatabase, it might contain additional informations.

As for the potential missing .dll they are likely in the somewhere in c:\app\instantclient_12_1

jacekkozik

Thank you for your help, I close the topic because I was able to build a plug. THANK YOU VERY MUCH.