[Gretl-users] Speed of "join"

Hi all, I am currently working on a rather large cross-sectional data set. Overall I have data comprising around half a Million individuals, about 225000 households and 26 countries. I tried to merge the different datasets, after dropping irrelevant variables before. But merging households (identified by HID) and countries (country) by "join" really takes a lot of time. Actually, joining one variable takes 25 minutes on my linux machine (2.6GHz). If I use STATA it may take a minute or so. Why does it take that long here? I am surprised because typically gretl operates pretty fast. Also, is there a way to merge all cross-sectional variables from the "outside" dataset with the "inner" one by a single command? At the moment one has to specify a join command for each variable separately, right? I am just asking out of curiosity as I am fine with the way it is currently implemented. Artur