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QSqlDatabase: QPSQL driver not loaded

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  • N Offline
    N Offline
    nkbartc
    wrote on last edited by
    #4

    PostgreSQL12.1 is for 64bit. Could this cause the problem?

    aha_1980A 1 Reply Last reply
    0
    • N nkbartc

      PostgreSQL12.1 is for 64bit. Could this cause the problem?

      aha_1980A Offline
      aha_1980A Offline
      aha_1980
      Lifetime Qt Champion
      wrote on last edited by
      #5

      @nkbartc said in QSqlDatabase: QPSQL driver not loaded:

      PostgreSQL12.1 is for 64bit. Could this cause the problem?

      If your app is 32 bit, then yes.

      Regards

      Qt has to stay free or it will die.

      N 1 Reply Last reply
      1
      • aha_1980A aha_1980

        @nkbartc said in QSqlDatabase: QPSQL driver not loaded:

        PostgreSQL12.1 is for 64bit. Could this cause the problem?

        If your app is 32 bit, then yes.

        Regards

        N Offline
        N Offline
        nkbartc
        wrote on last edited by
        #6

        @aha_1980

        OS: win10 64bit
        qt: 5.14.0
        kit: msvc2017 64bit
        PostgreSQL: 12.1

        I think I am supposed to use PostgreSQL 64bit, but I just tried with PostgreSQL 32bit. No luck.....

        1 Reply Last reply
        0
        • Christian EhrlicherC Offline
          Christian EhrlicherC Offline
          Christian Ehrlicher
          Lifetime Qt Champion
          wrote on last edited by
          #7

          Use dependency walker on qsqlpsql.dll to see what's missing. Maybe a msvcrt runtime

          Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
          Visit the Qt Academy at https://academy.qt.io/catalog

          N 1 Reply Last reply
          1
          • Christian EhrlicherC Christian Ehrlicher

            Use dependency walker on qsqlpsql.dll to see what's missing. Maybe a msvcrt runtime

            N Offline
            N Offline
            nkbartc
            wrote on last edited by
            #8

            @Christian-Ehrlicher

            I am using kit: msvc2017 64bit.

            I suppose that I should run dependency walker on qsqlpsql.dll at
            D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers ?

            Thanks

            1 Reply Last reply
            0
            • Christian EhrlicherC Offline
              Christian EhrlicherC Offline
              Christian Ehrlicher
              Lifetime Qt Champion
              wrote on last edited by
              #9

              @nkbartc said in QSqlDatabase: QPSQL driver not loaded:

              I suppose that I should run dependency walker on qsqlpsql.dll at

              yes

              Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
              Visit the Qt Academy at https://academy.qt.io/catalog

              1 Reply Last reply
              0
              • N Offline
                N Offline
                nkbartc
                wrote on last edited by
                #10

                2.png

                This is what I got

                aha_1980A 1 Reply Last reply
                0
                • N nkbartc

                  2.png

                  This is what I got

                  aha_1980A Offline
                  aha_1980A Offline
                  aha_1980
                  Lifetime Qt Champion
                  wrote on last edited by
                  #11

                  @nkbartc press Ok, then minimize the tree on the left side, so that only one level of dependencies is visible.

                  The yellow warnings are harmless, AFAIK.

                  Qt has to stay free or it will die.

                  N 1 Reply Last reply
                  1
                  • Christian EhrlicherC Offline
                    Christian EhrlicherC Offline
                    Christian Ehrlicher
                    Lifetime Qt Champion
                    wrote on last edited by
                    #12

                    Please take a look at the direct dependencies

                    Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                    Visit the Qt Academy at https://academy.qt.io/catalog

                    1 Reply Last reply
                    1
                    • aha_1980A aha_1980

                      @nkbartc press Ok, then minimize the tree on the left side, so that only one level of dependencies is visible.

                      The yellow warnings are harmless, AFAIK.

                      N Offline
                      N Offline
                      nkbartc
                      wrote on last edited by
                      #13

                      @aha_1980 @Christian-Ehrlicher

                      Like this? Sorry I am new to dependency walker.

                      1.png

                      aha_1980A 1 Reply Last reply
                      0
                      • N nkbartc

                        @aha_1980 @Christian-Ehrlicher

                        Like this? Sorry I am new to dependency walker.

                        1.png

                        aha_1980A Offline
                        aha_1980A Offline
                        aha_1980
                        Lifetime Qt Champion
                        wrote on last edited by
                        #14

                        @nkbartc Yes, like that.

                        Unfortunately(?) that looks all good, so this library (qsqlpsql.dll) does not seem to be the problem.

                        Regards

                        Qt has to stay free or it will die.

                        1 Reply Last reply
                        0
                        • N nkbartc

                          updated: this is what I got from QT_DEBUG_PLUGINS:

                          "The plugin 'D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlodbcd.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)" 
                                   not a plugin
                          QFactoryLoader::QFactoryLoader() looking at "D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll"
                          Found metadata in lib D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll, metadata=
                          {
                              "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
                              "MetaData": {
                                  "Keys": [
                                      "QPSQL7",
                                      "QPSQL"
                                  ]
                              },
                              "archreq": 0,
                              "className": "QPSQLDriverPlugin",
                              "debug": false,
                              "version": 331264
                          }
                          
                          
                          Got keys from plugin meta data ("QPSQL7", "QPSQL")
                          QFactoryLoader::QFactoryLoader() looking at "D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsqld.dll"
                          Found metadata in lib D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsqld.dll, metadata=
                          {
                              "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
                              "MetaData": {
                                  "Keys": [
                                      "QPSQL7",
                                      "QPSQL"
                                  ]
                              },
                              "archreq": 1,
                              "className": "QPSQLDriverPlugin",
                              "debug": true,
                              "version": 331264
                          }
                          
                          
                          "The plugin 'D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsqld.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)" 
                                   not a plugin
                          QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/nkbar/Documents/build-myRPG_alpha-Desktop_Qt_5_14_0_MSVC2017_64bit-Release/Server/release/sqldrivers" ...
                          Cannot load library D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsql.dll: The specified module could not be found.
                          QLibraryPrivate::loadPlugin failed on "D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll" : "Cannot load library D:\\Qt\\5.14.0\\msvc2017_64\\plugins\\sqldrivers\\qsqlpsql.dll: The specified module could not be found."
                          QSqlDatabase: QPSQL driver not loaded
                          QSqlDatabase: available drivers: QSQLITE QODBC QODBC3 QPSQL QPSQL7
                          QFactoryLoader::QFactoryLoader() checking directory path "D:/Qt/5.14.0/msvc2017_64/plugins/accessible" ...
                          QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/nkbar/Documents/build-myRPG_alpha-Desktop_Qt_5_14_0_MSVC2017_64bit-Release/Server/release/accessible" ...
                          QFactoryLoader::QFactoryLoader() checking directory path "D:/Qt/5.14.0/msvc2017_64/plugins/accessiblebridge" ...
                          QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/nkbar/Documents/build-myRPG_alpha-Desktop_Qt_5_14_0_MSVC2017_64bit-Release/Server/release/accessiblebridge" ...
                          

                          I checked "D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsqld.dll" and I did found the dll which the debugger reports as missing. And I am also confused about why it complains about "'D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll' uses incompatible Qt library.

                          The kit I am using is msvc2017 64bit and the postgre I downloaded is also for 64bit.


                          Errors:
                          QSqlDatabase: QPSQL driver not loaded
                          QSqlDatabase: available drivers: QSQLITE QODBC QODBC3 QPSQL QPSQL7

                          OS: win10 64bit
                          qt: 5.14.0
                          kit: msvc2017 64bit
                          PostgreSQL: 12.1

                          Sqlite works well, but my project just can't work with PostgreSQL.

                          I followed the official instruction: https://doc.qt.io/qt-5/sql-driver.html#qpsql

                          Got no error but still couldn't connect to PostgreSQL. Same error messages saying that "QPSQL driver not loaded".

                          I have also tried other solutions from here and stackoverflow and reinstall my qt 4 times, No luck still. I am really frustrated now and don't know what to do.

                          the .pro:

                          QT += core network gui widgets sql
                          
                          greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                          
                          CONFIG += c++11
                          
                          QTPLUGIN += QPSQL
                          QT_DEBUG_PLUGINS=1
                          
                          # 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
                          
                          #INCLUDEPATH += "D:\psql\include"
                          
                          #LIBS += "D:\psql\lib\libpq.lib"
                          
                          
                          SOURCES += \
                              battle.cpp \
                              creature.cpp \
                              player.cpp \
                              server.cpp \
                              servermain.cpp \
                              serverwindow.cpp \
                              serverworker.cpp
                          
                          HEADERS += \
                              battle.h \
                              creature.h \
                              data_structs.h \
                              player.h \
                              server.h \
                              serverwindow.h \
                              serverworker.h
                          
                          FORMS += \
                              serverwindow.ui
                          
                          # Default rules for deployment.
                          qnx: target.path = /tmp/$${TARGET}/bin
                          else: unix:!android: target.path = /opt/$${TARGET}/bin
                          !isEmpty(target.path): INSTALLS += target
                          
                          RESOURCES += \
                              resource.qrc
                          
                          
                          kshegunovK Offline
                          kshegunovK Offline
                          kshegunov
                          Moderators
                          wrote on last edited by
                          #15

                          @nkbartc said in QSqlDatabase: QPSQL driver not loaded:

                          I checked "D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsqld.dll" and I did found the dll which the debugger reports as missing. And I am also confused about why it complains about "'D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll' uses incompatible Qt library.

                          On windows debug and release libraries are different binaries and can't be loaded interchangeably (unlike with linux). You probably need to build the driver with debug.

                          Read and abide by the Qt Code of Conduct

                          1 Reply Last reply
                          1
                          • N nkbartc

                            2.png 1.png

                            I already did that. I am showing the pictures just in case if I did it wrong.

                            3 Offline
                            3 Offline
                            3KKK
                            wrote on last edited by
                            #16

                            @nkbartc Pointing to the dll in the bin library solved the issue for me. Change the path from D:\psql\lib to D:\psql\bin

                            1 Reply Last reply
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