One possible Debian-side solution could be changing the virtual-mysql-client-core and virtual-mysql-server-core to mariadb-client-core and mariadb-server-core, default-mysql-server to mariadb-server and removing the default-mysql-server-core dependency. That would cause dependency issues on systems that already have mysql-server-8 installed, but since CQRLOG does not seem to work with mysql anymore (only with mariadb), it should not be a big problem, at least in my opinion.
The other possible solution would be to patch this in Ubuntu. However, I am not sure whether the CQRLOG package has any Ubuntu maintainers and also it would probably break auto-sync of the package from Debian.
CQRLOG should also fix their MySQL 8 support if possible. That would probably be the best solution.
It looks like that there sadly are not other possible fixes to this issue.
So, as Dave Hibberd found out, the problem is that Ubuntu is shipping mysql-* as mysql-* and Debian is shipping mariadb-* as mysql-*.
See his original comment with more details here: https:/ /bugs.debian. org/cgi- bin/bugreport. cgi?bug= 1073790# 10
One possible Debian-side solution could be changing the virtual- mysql-client- core and virtual- mysql-server- core to mariadb-client-core and mariadb- server- core, default- mysql-server to mariadb-server and removing the default- mysql-server- core dependency. That would cause dependency issues on systems that already have mysql-server-8 installed, but since CQRLOG does not seem to work with mysql anymore (only with mariadb), it should not be a big problem, at least in my opinion.
The other possible solution would be to patch this in Ubuntu. However, I am not sure whether the CQRLOG package has any Ubuntu maintainers and also it would probably break auto-sync of the package from Debian.
CQRLOG should also fix their MySQL 8 support if possible. That would probably be the best solution.
It looks like that there sadly are not other possible fixes to this issue.