to pivot or not to pivot - schema design question I am implementing something similar to this schema
http://www.databaseanswers.org/data_models/event_reservations/index.htm

It occurs to me that the pivot table for Customer_Bookings would just keep on growing for the primary database interaction (insert Customer_Booking) and become a huge list. All the bookings, past, present and future, for each customer and each event will be contained in this table. The size of Customer_Bookings will be many times the size of any other table in the database and will only continue to get bigger with each new Event and Customer. None of the Customer_Bookings get deleted as new Events are created. Is this normal? Cause for concern? Can the table become too big over time? 

I am new to database design but couldn't find the information about this type of know-how anywhere...a link to a good reference would be appreciated too.
MySQL should not have trouble handling a large table like that.  You have it indexed (because of the foreign keys) so most queries against the table should use one of the indexes and be fairly fast even if there are a huge number of rows in the table.