Cant build QMYSQL driver on Ubuntu 22.04.2 LTS

SaadAli

I want to connect mysql database with Qt GUI. I dont have QMYSQL drivers installed so I started following the documentation here but can't seem to build it.

My ubuntu is

Ubuntu 22.04.2 LTS

I installed Qt creator using

sudo apt install qtcreator qtbase5-dev

I installed MySql using

sudo apt install mysql-server

I did could not find the required libmysqlclient.so file on my system so I used the following to get it:

sudo apt install libmysqlclient-dev

After that I followed the documentation as mentioned above. I had to run (qmake -- MYSQL_PREFIX=/usr/local) in the folder ($QTDIR/qtbase/src/plugins/sqldrivers) as stated in the documentation. I am running the command in (/usr/lib/x86_64-linux-gnu/qt5/plugins/sqldrivers) directory. When I run the command the output is:

$ qmake -- MYSQL_PREFIX=/usr/local

Usage: /usr/lib/qt5/bin/qmake [mode] [options] [files]

QMake has two modes, one mode for generating project files based on
some heuristics, and the other for generating makefiles. Normally you
shouldn't need to specify a mode, as makefile generation is the default
mode for qmake, but you may use this to test qmake on an existing project

Mode:
  -project       Put qmake into project file generation mode
                 In this mode qmake interprets [files] as files to
                 be added to the .pro file. By default, all files with
                 known source extensions are added.
                 Note: The created .pro file probably will 
                 need to be edited. For example add the QT variable to 
                 specify what modules are required.
  -makefile      Put qmake into makefile generation mode (default)
                 In this mode qmake interprets files as project files to
                 be processed, if skipped qmake will try to find a project
                 file in your current working directory

Warnings Options:
  -Wnone         Turn off all warnings; specific ones may be re-enabled by
                 later -W options
  -Wall          Turn on all warnings
  -Wparser       Turn on parser warnings
  -Wlogic        Turn on logic warnings (on by default)
  -Wdeprecated   Turn on deprecation warnings (on by default)

Options:
   * You can place any variable assignment in options and it will be *
   * processed as if it was in [files]. These assignments will be    *
   * processed before [files] by default.                            *
  -o file        Write output to file
  -d             Increase debug level
  -t templ       Overrides TEMPLATE as templ
  -tp prefix     Overrides TEMPLATE so that prefix is prefixed into the value
  -help          This help
  -v             Version information
  -early         All subsequent variable assignments will be
                 parsed right before default_pre.prf
  -before        All subsequent variable assignments will be
                 parsed right before [files] (the default)
  -after         All subsequent variable assignments will be
                 parsed after [files]
  -late          All subsequent variable assignments will be
                 parsed right after default_post.prf
  -norecursive   Don't do a recursive search
  -recursive     Do a recursive search
  -set <prop> <value> Set persistent property
  -unset <prop>  Unset persistent property
  -query <prop>  Query persistent property. Show all if <prop> is empty.
  -qtconf file   Use file instead of looking for qt.conf
  -cache file    Use file as cache           [makefile mode only]
  -spec spec     Use spec as QMAKESPEC       [makefile mode only]
  -nocache       Don't use a cache file      [makefile mode only]
  -nodepend      Don't generate dependencies [makefile mode only]
  -nomoc         Don't generate moc targets  [makefile mode only]
  -nopwd         Don't look for files in pwd [project mode only]

I have tried running qmake -- MYSQL_PREFIX=/usr/include/mysql aswell but I get the same result.
I dont have any directory such as $QTDIR/qtbase/src/plugins/sqldrivers ...

What should I do to build and install the driver for QMYSQL on ubuntu?

JonB

@SaadAli

@JonB said in Cant build QMYSQL driver on Ubuntu 22.04.2 LTS:

I cannot remember precisely what you have fetch from apt to get all the necessary components

Try apt install libqt-Tab-Tab. I think you need libqt5sql5-mysql?

Is there also a need for a libqsqlmysql.so? (Maybe that comes in the above package?)

JonB

@SaadAli
Running qmake is necessary if you are building Qt itself from sources and/or if you need to build the MySQL driver. However when you fetch everything via apt all you need is pre-supplied by Ubuntu. So you don't want to be doing any building/compiling yourself.

I cannot remember precisely what you have fetch from apt to get all the necessary components (don't forget you can type e.g. apt install libmysql and hit the Tab key twice to see available components). Do not proceed to any qmake steps. After your sudo apt install libmysqlclient-dev where are you in terms of runnability for a minimal program attempting to use QSql... stuff?

SaadAli

@JonB
I want to highlight according to the best of my knowledge that Qt Creator is normally installed by apt install qt5-default but I used sudo apt install qtcreator qtbase5-dev because Ubuntu 22.04.2 LTS doesn't have qt5-default in its apt repository.

Pressing Tab after typing apt install libmysql gives me the following options:

libmysql++3v5        libmysqlcppconn-dev  libmysql-ocaml
libmysqlclient21     libmysql++-dev       libmysql-ocaml-dev
libmysqlclient-dev   libmysql-diff-perl   
libmysqlcppconn7v5   libmysql++-doc

What should I install I have no idea.

After running sudo apt install libmysqlclient-dev I have achieved nothing. I get the same error when I print QSqlDatabase::lastError().text(). The error is as the following:

QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE
"Driver not loaded Driver not loaded"

JonB

@SaadAli

@JonB said in Cant build QMYSQL driver on Ubuntu 22.04.2 LTS:

I cannot remember precisely what you have fetch from apt to get all the necessary components

Try apt install libqt-Tab-Tab. I think you need libqt5sql5-mysql?

Is there also a need for a libqsqlmysql.so? (Maybe that comes in the above package?)

SaadAli

@JonB
Installing libqt5sql5-mysql made it work like a charm! Thank you @JonB ! That was all what I was missing.
But I don't know what is the role of libqsqlmysql.so. I dont know if installing libmysqlclient-dev made any difference. The only thing that happened after installing it was I got the file libqsqlmysql.so on my machine.

JonB

@SaadAli said in Cant build QMYSQL driver on Ubuntu 22.04.2 LTS:

The only thing that happened after installing it was I got the file libqsqlmysql.so on my machine.

Yep that's fine, it must be supplied in libqt5sql5-mysql package and that is what is needed.