QSqlDatabase: QPSQL driver not loaded

[Christian Ehrlicher]

@nkbartc said in QSqlDatabase: QPSQL driver not loaded:

Cannot load library D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsql.dll: The specified module could not be found.
QLibraryPrivate::loadPlugin failed on "D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll" : "Cannot load library D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsql.dll: The specified module could not be found."

You're most likely missing libpq.dll in your PATH / in your folder of your executable.

[nkbartc]

I already did that. I am showing the pictures just in case if I did it wrong.

[nkbartc]

PostgreSQL12.1 is for 64bit. Could this cause the problem?

[aha_1980]

@nkbartc said in QSqlDatabase: QPSQL driver not loaded:

PostgreSQL12.1 is for 64bit. Could this cause the problem?

If your app is 32 bit, then yes.

Regards

[nkbartc]

@aha_1980

OS: win10 64bit
qt: 5.14.0
kit: msvc2017 64bit
PostgreSQL: 12.1

I think I am supposed to use PostgreSQL 64bit, but I just tried with PostgreSQL 32bit. No luck.....

[Christian Ehrlicher]

Use dependency walker on qsqlpsql.dll to see what's missing. Maybe a msvcrt runtime

[nkbartc]

@Christian-Ehrlicher

I am using kit: msvc2017 64bit.

I suppose that I should run dependency walker on qsqlpsql.dll at
D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers ?

Thanks

[Christian Ehrlicher]

@nkbartc said in QSqlDatabase: QPSQL driver not loaded:

I suppose that I should run dependency walker on qsqlpsql.dll at

yes

[nkbartc]

This is what I got

[aha_1980]

@nkbartc press Ok, then minimize the tree on the left side, so that only one level of dependencies is visible.

The yellow warnings are harmless, AFAIK.

[Christian Ehrlicher]

Please take a look at the direct dependencies

[nkbartc]

@aha_1980 @Christian-Ehrlicher

Like this? Sorry I am new to dependency walker.

[aha_1980]

@nkbartc Yes, like that.

Unfortunately(?) that looks all good, so this library (qsqlpsql.dll) does not seem to be the problem.

Regards

[kshegunov]

@nkbartc said in QSqlDatabase: QPSQL driver not loaded:

I checked "D:\Qt\5.14.0\msvc2017_64\plugins\sqldrivers\qsqlpsqld.dll" and I did found the dll which the debugger reports as missing. And I am also confused about why it complains about "'D:/Qt/5.14.0/msvc2017_64/plugins/sqldrivers/qsqlpsql.dll' uses incompatible Qt library.

On windows debug and release libraries are different binaries and can't be loaded interchangeably (unlike with linux). You probably need to build the driver with debug.

[3KKK]

@nkbartc Pointing to the dll in the bin library solved the issue for me. Change the path from D:\psql\lib to D:\psql\bin