Problem with GetNthRecord

[clie boy]

Hi,

im kinda new here, im having problem with my portal and getnthrecord.

heres my database,

i have a main form called delivery w/ portal record.

in my protal i have item no, quantity, unit, description, unit price and amount.

and in my delivery i want a calculating field that will store item no. seperating with comma e.g. (2234A, 2334C, 3233C).

i can't get it work with getnthrecord. is there anyway to do this w/ out using script? i want this to be automated. sometimes our user doesnt use button to exit layout.

regards,

clie