Fixing a multiple warning “unknown column”

Question

I have a persistent multiple warning of \"unknown column\" for all types of commands (e.g., str(x) to installing updates on packages), and not sure how to debug this or fix

Answer 1

I have faced this issue when using the "dplyr" package.
For those facing this problem after using the "group_by" function in the "dplyr" library:

I have found that ungrouping the variables solves the unknown column warning problem. Sometimes I have had to iterate through the ungrouping several times until the problem is resolved.

Answer 2

I have been encountering the same problem, and although I don't know why it occurs, I have been able to pin down when it occurs, and thus prevent it from happening.

The issue seems to be with adding in a new column, derived from indexing, in a base R data frame vs. in a tibble data frame. Take this example, where you add a new column (age) to a base R data frame:

base_df <- data.frame(id = c(1:3), name = c("mary", "jill","steve"))

base_df$age[base_df$name == "mary"] <- 47

That works without returning a warning. But when the same is done with a tibble, it throws a warning (and consequently, I think causing the weird, seemingly unprovoked, multiple warning issue):

library(tibble)

tibble_df <- tibble(id = c(1:3), name = c("mary", "jill","steve"))

tibble_df$age[tibble_df$name == "mary"] <- 47

Warning message:
Unknown column 'age' 

There are surely better ways of avoiding this, but I have found that first creating a vector of NAs does the job:

tibble_df$age <- NA

tibble_df$age[tibble_df$name == "mary"] <- 47