Hi,

I have a lot of datasets to append, but Stata runs out of memory as the files are large contain a lot of variables. I tried the following, but it seems like the 'keep' function does not allow these options:

Code:
local f : dir . files "*.dta"

 display as result `"`f'"'

 append using `f' if year>2009
I just need two variables (IncomeGroup and HBP) and only for the years after 2009.

Please let me know if this possible to do.

Thank you.