Google "event join attendance site:forums.filemaker.com" Threads on these forums
Very informative thread with deSaint providing great help and demo databases for download that evolve over time
You need three tables:
Members::MemberID = Member_Event::MemberID
Event::EventID = Member_Event::EventID
The structure of the data in your spreadsheet presents a problem for getting your data in the correct place.
For Events, you can import this spreadsheet once and import just the first column into your events table.
For members, you can either import this spreadsheet once for each column of IDs or you can import it once into a temporary table and use a script to work with each column of data in the temporary table to build the table of members. You can set a Unique values, validate always validation rule on your Members::MemberID field and this will automatically filter out duplicate IDs during the import.
Forr Member_Event, you can do much the same, either import once for each column of member ID's or use the temp table approach. Using the one import for each column of members, you'd always map the first column to EventID, but map the MemberID field to a different column in the spreadsheet each time.
Once you have the data imported, see either DavidAnder's links and/or this demo file for ideas on how to work with the many to many relationship: https://www.dropbox.com/s/oyir7cs0yxmbn6i/ManyToManywDemoWExtras.fp7
It's strictly a fortunate coincidence that this demo file happens to be set up to match contacts to events.
I need to do something similar but by year only. I just want to know the year someone came on a trip.
So using your example then I am guessing I would do:
I want to track camping trips which usually occur over the summer by the year(s) someone has attended the campouts. My challenge is having something that allows me to print letters/labels to "all campers who came and camped in 2012" (i.e.).