How do i Generate _uud as a foreign Key in a loop


i am collecting data on households. First, i collect informations about the household representative, and in a loop (repeat) i collect informations about other members of the household. When i download data, i have 2 sheets. In the first sheet that contains informations about HH representative, i have a _uuid column. I would like to have the same column for each member in the second sheet. Something Like a foreign Key, (in relational databases). Any Idea please ?

I am using Xlsform.

Thank you !

Hello, can you share with us a sample of your data and how you download the data after data collection, when you download your data using briefcase you will have key and parent_key in both files (the main file and the repeated group sheet), this can be use to link the two files together.