I have a data frame allData that has 3 columns,and a data frame userData with 1 column.that every row of all data refers to a row of user data.
now I want to add userData column to my allData data frame.but I cant.
I tried some codes Like :
allData$user <- userData$userId
or:
cbind(allData , userData)
but non of theme do not work correctly.they produce a data with lots of columns unexpectedly.
how can I add user column to my allData data frame?
thank you.