Redmine

Noob here, please be gentle.

I've been walking through various tutorials getting set up on Ubuntu 12.04 LTS.

Finally got to the part where I download the code, and although I'd set up folders for:

redmine-2.3.4 redmine-2.3-stable redmine-2.4.3 redmine-2.4-stable

I now see we've got new versions.

Because I'm going to be trying out different plugins, I think I'd like to keep the above, as well as adding:

redmine-2.4.4 redmine-2.5.0 redmine-2.5-stable

My question is, can these various instances share the same MySQL DB?

Leaving plugins aside for the moment, what about vanilla Redmine instances?

And then separate question, if I see that a given plugin only adds columns, doesn't modify existing ones, can the same DB be shared across multiple instances with and without plugins?

Note none of this is production data obviously, but would like to have a sample data set in common.

A pointer to howto's or forum threads outlining export/import routines would be greatly appreciated, I've done some MySQL before but am new to the ruby stuff.

Thanks in advance. . .