Can't load sql drivers when configuring and building Qt 6.8.1 from source on linux/Ubuntu 24.04.1

KingWm

@jsulm I don't understand. I installed PostgreSQL from source. Might installing those packages interfere with my PG installation? Also, someone else mentioned that, so I checked and according to Google, I should reconfigure my PG building to include all the developer stuff. I wanted to build PostgreSQL, pgAmin, Qt & Qt Creator from source. If I can build the dev libs from source, I would rather do that.

This note here from the docs?
https://doc.qt.io/qt-6/sql-driver.html
Note: To build a driver plugin you need to have the appropriate client library for your Database Management System (DBMS). This provides access to the API exposed by the DBMS, and is typically shipped with it. Most installation programs also allow you to install "development libraries", and these are what you need. These libraries are responsible for the low-level communication with the DBMS. Also make sure to install the correct database libraries for your Qt architecture (32 or 64 bit).

Christian Ehrlicher

Why did you compile postgresql by yourself? Simply use the ones from your distro...
Where did you install postgresql to? If it's a non-default location you have to pass this to configure in a clean build dir.

KingWm

For practice. I installed PG from source, and all the others, because I wanted to learn how. Plus, I get a little more control over the specific version I use. I am setting up for a long term project and these are skills I need to learn.

PostgreSQL is installed here, and I do have it on the $PATH, but I guess the compiler is not checking the path?

/usr/local/postgresql/17.2/bin:
/usr/local/postgresql/17.2/lib:

SGaist

Hi,

PATH has nothing to do with library discovery. You're working on Linux, not Windows.
Use the -L argument to add additional paths to configure.

On a side note, stop working as root. There's no need for that for any build activity.

KingWm

This post is deleted!

KingWm

@SGaist I set the path variable because it is mentioned several times in the various docs I have read. I don't know if it is useful in this scenario or not.

I used -L arguments to pass the include and lib directories.

/usr/local/postgresql/17.2/include
/usr/local/postgresql/17.2/lib

In a new error message, it complained it couldn't find Ninja, so I added my Ninja path.

/usr/local/ninja/1.12.1

I am using sudo because nothing will work unless I use it. I presume it is because the source, build and install directories are all in /usr/local/.

I ran the following command, it fails with the same Postgres not found error.

../qt/configure -init-submodules -prefix /usr/local/qt/6.8.1 -sql-psql -L /usr/local/postgresql/17.2/lib -I /usr/local/postgresql/17.2/include -- -DCMAKE_BUILD_TYPE=Release -DCMAKE_GENERATOR=Ninja /usr/local/ninja/1.12.1

But when I run it WITHOUT the -sql-psql option, configure completes successfully with a few warnings. One is that it ignored the the path i provided for Ninja. Again, Ninja is on the path, but if it ignores that path I provide, I don't know how it is finding Ninja unless a sub-routine is providing it.

+ /usr/local/src/qt/qtbase/configure -top-level -prefix /usr/local/qt/6.8.1 -L /usr/local/postgresql/17.2/lib -I /usr/local/postgresql/17.2/include -- -DCMAKE_BUILD_TYPE=Release -DCMAKE_GENERATOR=Ninja /usr/local/ninja/1.12.1
'/usr/bin/cmake' '-DCMAKE_BUILD_TYPE=Release' '-DCMAKE_GENERATOR=Ninja' '/usr/local/ninja/1.12.1' '-DQT_INTERNAL_CALLED_FROM_CONFIGURE:BOOL=TRUE' '-DCMAKE_INSTALL_PREFIX=/usr/local/qt/6.8.1' '-DQT_EXTRA_INCLUDEPATHS=/usr/local/postgresql/17.2/include' '-DQT_EXTRA_LIBDIRS=/usr/local/postgresql/17.2/lib' '-G' 'Ninja' '/usr/local/src/qt'
CMake Warning:
  Ignoring extra path from command line:

   "/usr/local/ninja/1.12.1"

-- The CXX compiler identification is GNU 13.3.0
-- The C compiler identification is GNU 13.3.0

Christian Ehrlicher

Pass PostgreSQL_ROOT as written in the documentation: https://doc.qt.io/qt-6/sql-driver.html#how-to-build-the-qpsql-plugin-on-unix-and-macos

SGaist

@Christian-Ehrlicher said in Can't load sql drivers when configuring and building Qt 6.8.1 from source on linux/Ubuntu 24.04.1:

Pass PostgreSQL_ROOT as written in the documentation: https://doc.qt.io/qt-6/sql-driver.html#how-to-build-the-qpsql-plugin-on-unix-and-macos

My bad for the -L pointer ! Old Qt 5 habits.

@Christian-Ehrlicher is correct.

As for the sudo requirements, it's still wrong. The fact that you have stuff in /usr/local should have no influence unless there's a in issue with the files permissions that should be fixed.

As for PATH, it's only used to find executables on Linux, it has nothing to do with libraries.

KingWm

@jsulm I added libpq5 and libpq-dev packages with dependencies and my configuration completed successfully. Unfortunately, after waiting patiently for the build to complete, the install failed on the "last line", something about a missing a file. It caused me to reconsider my efforts. I am pretty sure this solved the original problem I posted about, sorry I didn't save the output.

I did check the docs and I didn'ts see those dependencies mentioned anywhere. I feel like the official docs should have those dependencies listed. Thank you.

KingWm

@Christian-Ehrlicher I was building it for the wrong reasons, I discovered. At the end of the day, I successfully built 3 packages and believe I would have eventually gotten PG done as well. I learned what I set out to learn and so I abandoned this project.

As it turned out, I had mis-configured my disks and my small OS drive filled up quickly. I had to start over with a fresh install and the decision to do things conventionally was easy. Thank you.

KingWm

@SGaist said in Can't load sql drivers when configuring and building Qt 6.8.1 from source on linux/Ubuntu 24.04.1:

On a side note, stop working as root. There's no need for that for any build activity.

I have noticed a pattern and clearly I need to change a bad habit. Thank you.