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.
This exercise is part of the course
Joining Data with data.table in R
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Right join
subjects[___]