Checks that columns in a data frame represent a unique key.
check_key(data, key = NULL, data_name = substitute(data))
| data | The data frame to check. |
|---|---|
| key | A character vector of the column names representing the key. |
| data_name | A string of the name of data. |
Throws an informative error or returns an invisible copy of the data.
By default (key = NULL) all the columns are checked.