If your Qt project utilizes an SQL database, there is a high chance that you'll run into an error during the build process due to missing binary files required to use SQL databases(missing QMYSQL driver). It is a very long, tedious process to build these files yourself so I have provided a link to a GitHub repository where you can find all the binary files that correlate to each Qt version.

This GitHub repository was created by "thecodemonkey86" and he/she maintains the releases of the necessary bin files for every new release of Qt. Instructions on where to move/copy the necessary files are provided as well:

https://github.com/thecodemonkey86/qt_mysql_driver/releases

This user also provides extra information on the problem and how you can build the files yourself from the source:

https://github.com/thecodemonkey86/qt_mysql_driver

Thanks for reading and I hope this helps.