Updating MySQL

[Marion Dumas]

Hello,
I am new to macports, so sorry for my perhaps naive question. I need
to build a database in mySQL so I'm checking I have the newest
version. Mysql is pre-installed on mac os x (new versions), but it was
also re-installed by macports automatically when I installed the port
dia a few weeks ago. So I ran selfupdate to get any mysql port update.
Now, when I search for mysql5, I find it under
/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_databases_mysql5/work/destroot/opt/local/bin/mysql5.
But when I launch mySQL from the terminal, it starts off mysql4 (which
I can find under both /opt/local/etc/mysql4 AND
/opt/local/var/macports/sources/rsync.macports.org/release/ports/databases/mysql4/).
So my question is the following:
1) Is it a problem that I have mysql installed in different places due
to the fact that it was pre-installed and then installed again
elsewhere by macports when installing another application?
2) How do I actually get the newer version to run instead of the older one?
Thank you for any help you could provide.
Best
Marion