We are going to update the ROOT version for our experiment software MpdRoot but I have discovered that the last ROOT versions support PostgreSQL clients v. 10.x only as decribed in the commit below (may be 10.x client doesn't work also but i can't check).
I tried to make queries to the experiment database from Ubuntu 18.04 with the last libpqxx-dev library (4.0.1+dfsg3-8) and from CentOS 7.4 with postgresql-devel (9.2.23-3) but I got the following message:
It is occurred because of this commit :
As PG_VERSION_NUM is located in the "pg_config.h" file, any TSQLStatement objects can't find this variable now, the above strange message is appeared and further execution is stopped.
P.S. If the location of "pg_config.h" file can be changed (as in PostgreSQL 10), may be it is more safe to check PostgreSQL (client) version in CMake.