Report warning if requested variable is not found
At present if a requested variable (e.g. specified with -v
) is not found in any input table, there is no error or warning message given. This is undesriable as UK Biobank does depricate variables and hence variables once used can 'disappear' from the source table.
I propose that at least a warning should always be added to the log when a variable is requested but not found in any input table. Additionally, an option could be added to turn the warning into an error, but there are presently too many options :) so maybe just the warning is fine.