Signups are stored in raidplanner_signups table. The raid ID and characters ID-s are connected there.
If you want a new table, the data must be filled there somehow. Probably you want a place where raid leaders can register who was there actually?
Sorry for asking that many, but I can’t see into you brain, and you talking about technical details without the actual problem/need.
Just tell me exactly what you want, but with details:
e.g.:
a.) I would like to see an attendance statistics. The attendance is registered by the raid leader.
OR
b.) I would like to see a statistics about signups and confirmation. A particular character was confirmed for raid x times in last month.
What you mean on attendance? As RaidPlanner itself doesn’t know how was there actually, how and who should put the data into RaidPlanner? Should it be a frontend view, or it needs to be accessible by admins only?