I just recently found out about the "hidden" random function in Tableau and I figured others might be interested in knowing about this. Therefore I am writing this short blog post.
If you do a normal search for "Random" in the function list when creating a calculated field, it will turn up empty. I have seen some creative workarounds to the issue https://community.tableau.com/docs/DOC-1474.
However, I just learned that if you type "Random()" in a calculated field, it will turn blue (like any other function) and will thereafter assign a random number between 0 and 1 to each row in the data set. (Illustrated in the picture below).