MariaDB client cannot be installed over MySQL on Debian ppc64le trusty

$ dpkg -l | grep -iE 'mysql|maria'

ii  libdbd-mysql-perl                  4.025-1ubuntu0.1                  ppc64el      Perl5 database interface to the MySQL database

ii  libmysqlclient18:ppc64el           5.5.54-0ubuntu0.14.04.1           ppc64el      MySQL database client library

ii  mysql-client-5.5                   5.5.54-0ubuntu0.14.04.1           ppc64el      MySQL database client binaries

ii  mysql-client-core-5.5              5.5.54-0ubuntu0.14.04.1           ppc64el      MySQL database core client binaries

ii  mysql-common                       5.5.54-0ubuntu0.14.04.1           all          MySQL database common files, e.g. /etc/mysql/my.cnf

ii  mysql-server                       5.5.54-0ubuntu0.14.04.1           all          MySQL database server (metapackage depending on the latest version)

ii  mysql-server-5.5                   5.5.54-0ubuntu0.14.04.1           ppc64el      MySQL database server binaries and system database setup

ii  mysql-server-core-5.5              5.5.54-0ubuntu0.14.04.1           ppc64el      MySQL database server binaries

$ sudo apt-get install mariadb-client

Reading package lists... Done

Building dependency tree       

Reading state information... Done

Some packages could not be installed. This may mean that you have

requested an impossible situation or if you are using the unstable

distribution that some required packages have not yet been created

or been moved out of Incoming.

The following information may help to resolve the situation:

The following packages have unmet dependencies:

 mariadb-client : Depends: mariadb-client-10.2 (>= 10.2.11+maria~trusty) but it is not going to be installed

E: Unable to correct problems, you have held broken packages.

$ sudo apt-get install mariadb-server mariadb-client  

Reading package lists... Done

Building dependency tree       

Reading state information... Done

Some packages could not be installed. This may mean that you have

requested an impossible situation or if you are using the unstable

distribution that some required packages have not yet been created

or been moved out of Incoming.

The following information may help to resolve the situation:

The following packages have unmet dependencies:

 mariadb-client : Depends: mariadb-client-10.2 (>= 10.2.11+maria~trusty) but it is not going to be installed

 mariadb-server : Depends: mariadb-server-10.2 (>= 10.2.11+maria~trusty) but it is not going to be installed

E: Unable to correct problems, you have held broken packages.

$ sudo apt-get install mariadb-client-10.2

Reading package lists... Done

Building dependency tree       

Reading state information... Done

The following extra packages will be installed:

  libreadline5 mariadb-client-core-10.2 mariadb-common mysql-common

The following packages will be REMOVED:

  mysql-client-5.5 mysql-client-core-5.5 mysql-server mysql-server-5.5

  mysql-server-core-5.5

The following NEW packages will be installed:

  libreadline5 mariadb-client-10.2 mariadb-client-core-10.2 mariadb-common

The following packages will be upgraded:

  mysql-common

1 upgraded, 4 newly installed, 5 to remove and 76 not upgraded.

Need to get 91.6 kB/1,858 kB of archives.

After this operation, 60.7 MB disk space will be freed.

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