The final project in 214 requires rbind'ing multiple datasets. The students learn joins in 221, so they all try to use joins (a horizontal operation) to accomplish concatenation (vertical). It can work if you use a full join and join on ALL columns, but I'm afraid that confuses their conceptual model. Should I teach rbind() in 214? Or should it get covered in 221?
The final project in 214 requires rbind'ing multiple datasets. The students learn joins in 221, so they all try to use joins (a horizontal operation) to accomplish concatenation (vertical). It can work if you use a full join and join on ALL columns, but I'm afraid that confuses their conceptual model. Should I teach rbind() in 214? Or should it get covered in 221?