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QSqlQuery::prepare: database not open

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #6

    Hi,

    Are you running phpmyadmin on the same machine as the MySQL server ?

    Are you running your application on the same machine as the server ?

    If no to the second question, then did you correctly configure your MySQL server to accept external connections ? And also don't forget to secure them.

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

    R 1 Reply Last reply
    1
    • SGaistS SGaist

      Hi,

      Are you running phpmyadmin on the same machine as the MySQL server ?

      Are you running your application on the same machine as the server ?

      If no to the second question, then did you correctly configure your MySQL server to accept external connections ? And also don't forget to secure them.

      R Offline
      R Offline
      RekTek249
      wrote on last edited by
      #7

      @SGaist I'm hosting the sql server on a website. It's a hosting website so I guess it's a linux server ? I'm running phpmyadmin on my windows 10 computer.

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #8

        Then check that you are correctly using the same user name, password as you are using in PHPMyAdmin.

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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        • SGaistS SGaist

          Then check that you are correctly using the same user name, password as you are using in PHPMyAdmin.

          R Offline
          R Offline
          RekTek249
          wrote on last edited by
          #9

          @SGaist It is the correct one i checked that before asking it here...

          1 Reply Last reply
          0
          • SGaistS Offline
            SGaistS Offline
            SGaist
            Lifetime Qt Champion
            wrote on last edited by
            #10

            What exact error message do you get from your QSqlDatabase object ?

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            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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            • R RekTek249

              Hey, I started SQL today and I was wondering why it says db isn't open. Note: I had trouble with another error saying the driver wasn't found or something and I added a bunch of files to system PATH. Here is my code.

              void w::database(){
              QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
                  db.setHostName("Host");
                  db.setDatabaseName("Name");         /* In my real code, I set the real
                  db.setUserName("Username");               stuff here */
                  db.setPassword("Password");
              
                  if (db.open())                                             
                  {                                                                        
                      QMessageBox msgBox;                         
                      msgBox.setText("DB OPENED");          
                      msgBox.exec();
              
                  }
              
              
                  QSqlQuery query(db);
                  query.prepare("INSERT INTO person (Username, Password, summ, Email) "  
                                    "VALUES (:user, :pass, :summ, :mail)");
                  query.bindValue(":user", Username);          // I do have variables set earlier
                  query.bindValue(":pass", Password);
                  query.bindValue(":summ", summ);
                  query.bindValue(":mail", Email);
                  query.exec();
              
              }
              

              For some reasons, when I press the button (which launch this method) if I have the db.open part, It "doesn't respond". Help anyone... I searched on internet but didn't find anything that solved my problem...
              Thanks

              Taz742T Offline
              Taz742T Offline
              Taz742
              wrote on last edited by
              #11

              @RekTek249

                  QSqlQuery query(db);
                  query.prepare("INSERT INTO person (Username, Password, summ, Email) "  
                                    "VALUES (:user, :pass, :summ, :mail)");
                  query.bindValue(":user", Username);          // I do have variables set earlier
                  query.bindValue(":pass", Password);
                  query.bindValue(":summ", summ);
                  query.bindValue(":mail", Email);
                  query.exec();
              

              The mistake is not giving you anything error?

              please #include "QSqlError" and

               if (db.open())                                             
                  {                                                                        
                      QMessageBox msgBox;                         
                      msgBox.setText("DB OPENED");          
                      msgBox.exec();
              
                  }
              else{
                     qDebug() << db.lastError()
               }
              

              By doing so we can understand what the problem is about anyway...

              Do what you want.

              1 Reply Last reply
              0
              • R Offline
                R Offline
                RekTek249
                wrote on last edited by RekTek249
                #12

                @Taz742 QSqlError("2003", "QMYSQL: Unable to connect", "Can't connect to MySQL server on 'adress.here' (10060)")
                Is the error...

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                • SGaistS Offline
                  SGaistS Offline
                  SGaist
                  Lifetime Qt Champion
                  wrote on last edited by
                  #13

                  Did you check that the user you are using to connect to the database can be used for remote connections ?

                  Interested in AI ? www.idiap.ch
                  Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                  R 1 Reply Last reply
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                  • SGaistS SGaist

                    Did you check that the user you are using to connect to the database can be used for remote connections ?

                    R Offline
                    R Offline
                    RekTek249
                    wrote on last edited by
                    #14

                    @SGaist It can.... What is the "2003" and 10060 meaning ? is 2003 the port ?

                    Taz742T 1 Reply Last reply
                    0
                    • R Offline
                      R Offline
                      RekTek249
                      wrote on last edited by
                      #15

                      I tried it on another server and it gives the following error..

                      QSqlError("2005", "QMYSQL: Unable to connect", "Unknown MySQL server host 'mysql.hostinger.fr' (0)")
                      QSqlQuery::prepare: database not open
                      
                      the_T 1 Reply Last reply
                      0
                      • R RekTek249

                        I tried it on another server and it gives the following error..

                        QSqlError("2005", "QMYSQL: Unable to connect", "Unknown MySQL server host 'mysql.hostinger.fr' (0)")
                        QSqlQuery::prepare: database not open
                        
                        the_T Offline
                        the_T Offline
                        the_
                        wrote on last edited by
                        #16

                        @RekTek249
                        Again: are you sure you are allowed to establish a remote connection to the database?

                        • check user permission
                        • check if port is correct
                        • check if port is reachable from remote

                        -- No support in PM --

                        1 Reply Last reply
                        2
                        • R RekTek249

                          @SGaist It can.... What is the "2003" and 10060 meaning ? is 2003 the port ?

                          Taz742T Offline
                          Taz742T Offline
                          Taz742
                          wrote on last edited by
                          #17

                          @RekTek249 said in QSqlQuery::prepare: database not open:

                          It can.... What is the "2003" and 10060 meaning ? is 2003 the port ?

                          2003 is not a port name, so let's say the title of the problem.

                          Do what you want.

                          the_T 1 Reply Last reply
                          0
                          • Taz742T Taz742

                            @RekTek249 said in QSqlQuery::prepare: database not open:

                            It can.... What is the "2003" and 10060 meaning ? is 2003 the port ?

                            2003 is not a port name, so let's say the title of the problem.

                            the_T Offline
                            the_T Offline
                            the_
                            wrote on last edited by
                            #18

                            @Taz742
                            It's not a "title", just an qt internal error number. Same with the other code that is a mysql internal error code

                            -- No support in PM --

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                            • SGaistS Offline
                              SGaistS Offline
                              SGaist
                              Lifetime Qt Champion
                              wrote on last edited by
                              #19

                              To add to @the_ : the error state that mysql.hostinger.fr is an unknown host. Looks like you are giving the wrong address.

                              Interested in AI ? www.idiap.ch
                              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                              R 1 Reply Last reply
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                              • SGaistS SGaist

                                To add to @the_ : the error state that mysql.hostinger.fr is an unknown host. Looks like you are giving the wrong address.

                                R Offline
                                R Offline
                                RekTek249
                                wrote on last edited by
                                #20

                                @SGaist When I go to the "remote mysql" part of the site, it gives an access host... do i gotta use this as the hostname ?

                                R 1 Reply Last reply
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                                • R RekTek249

                                  @SGaist When I go to the "remote mysql" part of the site, it gives an access host... do i gotta use this as the hostname ?

                                  R Offline
                                  R Offline
                                  RekTek249
                                  wrote on last edited by RekTek249
                                  #21

                                  @RekTek249 If that's what i do, it gives that error:

                                  QSqlError("1045", "QMYSQL: Unable to connect", "Access denied for user 'rektek_write'@'*ip here*.' (using password: YES)")
                                  

                                  If it's a permission problem, what do I need to do ? I have the insert one because that's the only thing I need to do...

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                                  0
                                  • SGaistS Offline
                                    SGaistS Offline
                                    SGaist
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #22

                                    Is this user authorised to access the database from outside that machine ?

                                    Interested in AI ? www.idiap.ch
                                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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                                    • SGaistS SGaist

                                      Is this user authorised to access the database from outside that machine ?

                                      R Offline
                                      R Offline
                                      RekTek249
                                      wrote on last edited by
                                      #23

                                      @SGaist Well it's a website host.... They wouldn't allow you to create hosts that can only connect on that machine i guess.

                                      1 Reply Last reply
                                      0
                                      • SGaistS Offline
                                        SGaistS Offline
                                        SGaist
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #24

                                        That I don't know, you should ask them.

                                        Interested in AI ? www.idiap.ch
                                        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                        R 1 Reply Last reply
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                                        • SGaistS SGaist

                                          That I don't know, you should ask them.

                                          R Offline
                                          R Offline
                                          RekTek249
                                          wrote on last edited by
                                          #25

                                          @SGaist Alright... I checked something and apparently for remote you need the user's ip. The control panel needs the ip so I guess I can't make this application public because they wont be able to access the database ?

                                          1 Reply Last reply
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