You can also use GetAllRowsmethod to get all the column at once.
For example, if my table is something like this :
I can use values (which contains list of rows and each rows contains list of item) from GetAllRows and do like this :
Internally inside program GetColumn method use similar idea to fetch a particular column for you. That’s why I always suggest users to use GetAllRows method than GetColumn. That will help you to get all the column you need quickly and it save more responses.