I am trying to get the course graduation rate using Canvas data and Tableau. We already have all the tables in a Postgres DB (we are not using Amazon Redshift). Right now I have course names, student names and students enrolled in a particular course, quizzes and other things. I am wondering if there is any better way to find out course graduation rate without doing multiple joins in the tables. The only way I found so far is add all students quiz scores and divide with possible_points for the quizzes.