[Gretl-users] how to match observations with 'join' and gdt files

Hi, I ran into a problem when using 'join' with a native gdt file (with time series data). (Background: support for native gdt files was recently added to the join command, on my request I am afraid.) The sample and/or workfile ranges did not coincide, stopping the data import. With a text file one would have to use the --tkey option or something like that, as explained in the join chapter of the guide. But I could not find an explanation of how to do that with a native file. thanks, sven