You can check if they are infact installed
yum list installed | grep 'mariadb\|mysql'
I believe as of Centos 7 Mariadb was included in the centos repo.
If Mariadb is present, based on the message above the library may need to be removed
One other one,
rpm -qa | grep 'maria\|sql'
Glad to hear it was a simple fix.
Thanks, you also have a good weekend!
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