What does "psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql)" actually mean?

I have a question regarding following output: [nikola@192 ~] $ sudo su - postgres [postgres@192 ~] $ psql dvdrental postgres psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql) psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql) psql (11.7, server 11.8) Type "help" for help. dvdrental=# What do following two messages stand for and why? Messages I am asking about: 1) psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql) 2) psql (11.7, server 11.8) - BTW, for this psql --version command I get following output: psql (PostgreSQL) 11.8 (**had to install** PostgreSQL Server version 11.7 in order to perform command such as \dt and \l) ...and also this output: > postgres=# select * FROM version(); > version > -------------------------------------------------------------------------------------------------------- > PostgreSQL 11.8 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 9.3.1 20200408 (Red Hat 9.3.1-2), 64-bit > (1 row) P.S. I'm running PostgreSQL 11.8 on Fedora 30. **UPDATE1:** As requested by @LaurenzAlbe output for rpm -qa|grep postgres command is: [nikola@192 ~] $ rpm -qa|grep postgres postgresql-11.7-2.fc30.x86_64 postgresql11-11.8-1PGDG.f30.x86_64 postgresql11-libs-11.8-1PGDG.f30.x86_64 postgresql11-server-11.8-1PGDG.f30.x86_64 postgresql-server-11.7-2.fc30.x86_64 **UPDATE2**: I've ran dnf remove postgresql postgresql-server command -> databases are still there and I can access them via **pgAdmin4** and **psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql** message is no longer showing up. But, there is now new issue -> when I access **postgres shell** in terminal using sudo su - postgres command and then perform psql some-database-name postgres I get message > bash: psql: command not found...
> Install package 'postgresql' to provide command 'psql'? [N/y] I presume this is asking me to install AGAIN **Fedora package** which in 1st place I am trying to get rid off (to not show psql: */usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql)* message). Any suggestion how to solve this without installing Fedora package but from **PostgreSQL Global Development group**? **P.S.** BTW, I've installed Postgres server by following [this](https://computingforgeeks.com/how-to-install-postgresql-on-fedora/) link which uses PGDG packages (but something didn't work right on my machine and I guess I've been offered by Fedora30 OS to install Fedora packages which is obviously what I did :) ).