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.
Latihan ini adalah bagian dari kursus
Joining Data with data.table in R
Latihan interaktif praktis
Cobalah latihan ini dengan menyelesaikan kode contoh berikut.
# Right join
subjects[___]