Multi-column keys
Two new datasets are available in your R session:
subjects: contains the subject each student is taking each semester this yearlocations: contains the room allocations for each subject
Your goal is to build a new data.table with the locations of each subject for each student.
Diese Übung ist Teil des Kurses
Joining Data with data.table in R
Interaktive Übung
Versuche dich an dieser Übung, indem du diesen Beispielcode vervollständigst.
# Right join
subjects[___]