Summaries for groups of records
I'm putting together a course database to manage the grades of thousands of students covering years of courses. When sending out reports to them and for my own viewing, I like to see summary statistics, such as the number of students in the class and the average, median and standard deviation of the grades for each assignment beside the grade of the student whose record I am viewing. I know that this is easy to do using summary fields but the summaries depend on the found set and only show the correct stats for the class of the student in question if the found set is that class; if I look up one particular student, the found set will be that one record and the summary fields will show the grades of that one student rather than the class. I'm thinking to creating a self-join and using summaries of portals to do the job, but I am wondering whether there are other ways I should look into. I know that some dynamic calculations slow down FileMaker, and I'd like to keep the database speedy.
Any thoughts would be much appreciated,