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Selecting data from mysql using qt?

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  • D Offline
    D Offline
    Dii
    wrote on 11 Oct 2010, 21:47 last edited by
    #25

    Well, it should make no problem to have SQL query before exec(), at least I don't have any problem with that.

    Let's get back to square one:
    You said if you uncomment the
    @bool ok = db.open();@
    then your program hangs. Can we see the value of 'ok'?
    @qDebug() << ok;@
    My guess is probably you have problems granting the rights in mysql when you've created the table... have you made
    @GRANT ALL ON testTwo.* to 'root'at'localhost' IDENTIFIED BY 'somepassword';@
    (Ouch please replace the 'at' with the 'at' sign, the forum motor uses it for code tags, I don't know how to write it... I hope it's not confusing.
    I'm not sure if you can do it with empty password, I guess yes, but I never do that.)

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    • D Offline
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      doforumda
      wrote on 12 Oct 2010, 05:49 last edited by
      #26

      i now put password for root at localhost.
      when i place qDebug() << ok then it displays this
      @
      false
      QSqlQuery::exec: database not open
      @

      false might be the value of ok.

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      • L Offline
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        lyuts
        wrote on 12 Oct 2010, 08:16 last edited by
        #27

        Are you able to connect to your DB from shell?

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

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        • D Offline
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          doforumda
          wrote on 12 Oct 2010, 08:21 last edited by
          #28

          i dont know how to connect to my DB from shell. I install xampp which is easy for me to manage my databases.
          how can i connect from shell?

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          • L Offline
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            lyuts
            wrote on 12 Oct 2010, 08:25 last edited by
            #29

            @mysql -h host -D dbname -u user@

            I guess your can omit host parameter if you are connecting to localhost. You might need to specify "-p password" switch also (depends on mysql configuration).

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

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            • D Offline
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              doforumda
              wrote on 12 Oct 2010, 08:30 last edited by
              #30

              i think i did not install any mysql client. bcause it displays this output
              @
              root@zafar-laptop:/# mysql -h localhost -D testTwo -u root -p xxxxxx
              The program 'mysql' can be found in the following packages:

              • mysql-client-core-5.1
              • mysql-client-5.0
              • mysql-cluster-client-5.1
                Try: apt-get install <selected package>
                @
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              • L Offline
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                lyuts
                wrote on 12 Oct 2010, 08:31 last edited by
                #31

                Run
                @dpkg --list | grep mysql@
                and post the output for this command.

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

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                • D Offline
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                  doforumda
                  wrote on 12 Oct 2010, 08:35 last edited by
                  #32

                  here it is
                  @
                  root@zafar-laptop:/# dpkg --list | grep mysql
                  ii libmysqlclient-dev 5.1.41-3ubuntu12.6 MySQL database development files
                  ii libmysqlclient16 5.1.41-3ubuntu12.6 MySQL database client library
                  ii mysql-common 5.1.41-3ubuntu12.6 MySQL database common files (e.g. /etc/mysql

                  @

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                  • L Offline
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                    lyuts
                    wrote on 12 Oct 2010, 08:37 last edited by
                    #33

                    How did you create your database? I don't see any mysql server either.

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

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                    • D Offline
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                      doforumda
                      wrote on 12 Oct 2010, 08:40 last edited by
                      #34

                      well i download xampp and install it. i created database using phpmyadmin.

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                        doforumda
                        wrote on 12 Oct 2010, 08:42 last edited by
                        #35

                        i install xampp in this folder /opt/lampp

                        and my database is in /opt/lampp/var/mysql

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                        • L Offline
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                          lyuts
                          wrote on 12 Oct 2010, 08:44 last edited by
                          #36

                          Ok, I see. What is the location of your XAMPP installation? try to find the mysql binary there. And use the whole path (since I assume it is not in PATH) when connecting, i.e.

                          @/path/to/xampp/bin/mysql -D dbname -u username@

                          UPD: Didn't notice the location of xampp. then try (I guess it would be like this) @/opt/lampp/bin/mysql@

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

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                          • D Offline
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                            doforumda
                            wrote on 12 Oct 2010, 09:00 last edited by
                            #37

                            now here it what it says
                            @
                            root@zafar-laptop:/# /opt/lampp/bin/mysql -D testTwo -h localhost -u root -p 123456
                            Enter password:
                            ERROR 1049 (42000): Unknown database '123456'
                            @
                            i am providing the right pw

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                            • L Offline
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                              lyuts
                              wrote on 12 Oct 2010, 09:01 last edited by
                              #38

                              Try not passing -p switch. I guess you will be prompted to type in your password.
                              or
                              @/opt/lampp/bin/mysql -u root testTwo@

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

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                              • D Offline
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                                doforumda
                                wrote on 12 Oct 2010, 09:08 last edited by
                                #39

                                now it output is Access Denied
                                @
                                root@zafar-laptop:/# /opt/lampp/bin/mysql -u root testTwo
                                ERROR 1045 (28000): Access denied for user 'root'at'localhost' (using password: NO)
                                @

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                                • L Offline
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                                  lyuts
                                  wrote on 12 Oct 2010, 09:12 last edited by
                                  #40

                                  I'm sorry i just confused you with my last post.

                                  @/opt/lampp/bin/mysql -u root -p 123456 testTwo@

                                  I thought that mysql would prompt you but it didn't.

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

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                                  • D Offline
                                    D Offline
                                    Dii
                                    wrote on 12 Oct 2010, 09:16 last edited by
                                    #41

                                    Do it this way, then it will prompt for a password:

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

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                                    • D Offline
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                                      doforumda
                                      wrote on 12 Oct 2010, 09:16 last edited by
                                      #42

                                      i got a big ouput here but i have not seen any errors in this. when i try to post whole output this forum didnt allow me to post more than 6000 characters

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                                      • L Offline
                                        L Offline
                                        lyuts
                                        wrote on 12 Oct 2010, 09:18 last edited by
                                        #43

                                        Cut it into pieces or use something like pastebin.

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

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                                        • D Offline
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                                          doforumda
                                          wrote on 12 Oct 2010, 09:21 last edited by
                                          #44

                                          ok here it is
                                          @
                                          root@zafar-laptop:/# /opt/lampp/bin/mysql -u root -p 123456 testTwo
                                          /opt/lampp/bin/mysql Ver 14.14 Distrib 5.1.41, for pc-linux-gnu (i686) using EditLine wrapper
                                          Copyright 2000-2008 MySQL AB, 2008 Sun Microsystems, Inc.
                                          This software comes with ABSOLUTELY NO WARRANTY. This is free software,
                                          and you are welcome to modify and redistribute it under the GPL license
                                          Usage: /opt/lampp/bin/mysql [OPTIONS] [database]
                                          -?, --help Display this help and exit.
                                          -I, --help Synonym for -?
                                          --auto-rehash Enable automatic rehashing. One doesn't need to use
                                          'rehash' to get table and field completion, but startup
                                          and reconnecting may take a longer time. Disable with
                                          --disable-auto-rehash.
                                          -A, --no-auto-rehash
                                          No automatic rehashing. One has to use 'rehash' to get
                                          table and field completion. This gives a quicker start of
                                          mysql and disables rehashing on reconnect. WARNING:
                                          options deprecated; use --disable-auto-rehash instead.
                                          -B, --batch Don't use history file. Disable interactive behavior.
                                          (Enables --silent)
                                          --character-sets-dir=name
                                          Directory where character sets are.
                                          --column-type-info Display column type information.
                                          -c, --comments Preserve comments. Send comments to the server. The
                                          default is --skip-comments (discard comments), enable
                                          with --comments
                                          -C, --compress Use compression in server/client protocol.
                                          -#, --debug[=#] This is a non-debug version. Catch this and exit
                                          --debug-check Check memory and open file usage at exit.
                                          -T, --debug-info Print some debug info at exit.
                                          -D, --database=name Database to use.
                                          --default-character-set=name
                                          Set the default character set.
                                          --delimiter=name Delimiter to be used.
                                          -e, --execute=name Execute command and quit. (Disables --force and history
                                          file)
                                          -E, --vertical Print the output of a query (rows) vertically.
                                          -f, --force Continue even if we get an sql error.
                                          -G, --named-commands
                                          Enable named commands. Named commands mean this program's
                                          internal commands; see mysql> help . When enabled, the
                                          named commands can be used from any line of the query,
                                          otherwise only from the first line, before an enter.
                                          Disable with --disable-named-commands. This option is
                                          disabled by default.
                                          -g, --no-named-commands
                                          Named commands are disabled. Use * form only, or use
                                          named commands only in the beginning of a line ending
                                          with a semicolon (;) Since version 10.9 the client now
                                          starts with this option ENABLED by default! Disable with
                                          '-G'. Long format commands still work from the first
                                          line. WARNING: option deprecated; use
                                          --disable-named-commands instead.
                                          -i, --ignore-spaces Ignore space after function names.

                                          @

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