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    Selecting data from mysql using qt?

    General and Desktop
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    • D
      Dii last edited by

      lol, don't be write only :)

      /opt/lampp/bin/mysql -D testTwo -h localhost -u root -p

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      • D
        Dii last edited by

        BTW if you do this, AND it's working, you end up in mysql command line interface, you can get out with 'exit'

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        • D
          doforumda last edited by

          sorry i couldnt notice Dii user

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          • L
            lyuts last edited by

            Wow, mysql is full of surprises. Never got those with psql. ¤ Dii ¤, does it have \q command?

            I'm a rebel in the S.D.G.

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            • D
              doforumda last edited by

              yes i get into mysql command line

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              • D
                doforumda last edited by

                whats the reason that my database is not opening in qt?

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                • D
                  Dii last edited by

                  lyuts: yes \q is working too

                  doforumda: ok, so get into the mysql comand line with the command above

                  /opt/lampp/bin/mysql -D testTwo -h localhost -u root -p

                  and then do this:

                  grant all on testTwo.* to 'root'@'localhost' ;

                  Then we have a working mysql, and the rights are granted, we can get back to your Qt program.

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                  • L
                    lyuts last edited by

                    I hope the next post will be like "Hooray, I got it working!!!" :)

                    I'm a rebel in the S.D.G.

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                    • D
                      doforumda last edited by

                      there is an error in sql syntax
                      @
                      mysql> grant all on testTwo.* to ‘root’@’localhost’;
                      ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '��root’@’localhost’' at line 1
                      @

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                      • D
                        Dii last edited by

                        Ok, back to your Qt program:

                        @#include <QApplication>
                        #include <QtSql>

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

                        QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
                        db.setDatabaseName("testTwo");
                        db.setUserName("root");
                        db.setPassword("");
                        db.setHostName("localhost");
                        
                        bool ok = db.open();
                        qDebug() << ok;
                        
                        QSqlQuery query;
                        query.exec&#40;"SELECT firstname,lastname FROM testTable"&#41;;
                        while(query.next()) {
                            QString firstName = query.value(0).toString();
                            QString secondName = query.value(1).toString();
                            qDebug() << "First Name: " << firstName << "Last Name:" << secondName;
                            qDebug() << db.lastError();
                        }
                        return 0;
                        

                        }@

                        Notice, we don't set a password here.
                        The end is 'return 0' instead of 'a.exec()', and it won't hang. The exec() starts the main event loop, and you don't use it here...

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                        • L
                          lyuts last edited by

                          I think you need to check apostrophes in that command.

                          I'm a rebel in the S.D.G.

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                          • D
                            Dii last edited by

                            ok, you have wrong apostrof type there. I mean this >> '

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                            • D
                              doforumda last edited by

                              i tried without apostrophes as well but same error

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                              • D
                                Dii last edited by

                                nope, you had ` before the root and not '
                                that was the error

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                                • D
                                  Dii last edited by

                                  ok, wait a second, I checked it in the meantime and it won't work without password, stay tuned, I post the right command

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                                  • D
                                    doforumda last edited by

                                    you mean like this
                                    grant all on testTwo.* to root@localhost ;
                                    if yes it also displaying same error

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                                    • D
                                      Dii last edited by

                                      so, here we go:

                                      grant all on testTwo.* to 'root'@'localhost' identified by 'password';

                                      Make the right apostrophes! :) You have to set the password in your Qt app too.

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                                      • D
                                        Dii last edited by

                                        ok, wait I see

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                                        • D
                                          Dii last edited by

                                          the Devnet's forum motor changes the apostrophes somehow... use the straight apostrophes everywhere
                                          I mean this @'@

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                                          • D
                                            doforumda last edited by

                                            mysql query did its job its now successful but when i use qt code and try to make it run it displays same error

                                            @
                                            Starting /home/zafar/c++/dbExample-build-desktop/dbExample...
                                            false
                                            QSqlQuery::exec: database not open
                                            /home/zafar/c++/dbExample-build-desktop/dbExample exited with code 0
                                            @

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