Well very recently I had a real bad time configuring MySQL workbench on my system.
Whenever I try to connect to the database using the "Connection Manager", it displays the error "libmysqlclient_r.so" not found".
This happens to be a known bug in the workbench. Just dont linger around.... Simply create a soft link to the already existing libmysqlclient_r.so.16.0.0 or may be u have another version 15.0.0.
sudo ln -sf /usr/lib/libmysqlclient_r.so.16.0.0 /usr/lib/libmysqlclient_r.so
or if u have libmysqlclient 15.0.0 then
sudo ln -sf /usr/lib/libmysqlclient_r.so.15.0.0 /usr/lib/libmysqlclient_r.so
The worbench will work like a charm.