Keep track of changes in Master / Child tables

Hello Masters,

I have a form that has 1 master and 6 child sections to enter / update information. There are multiple users who updates the form.

I want a way to keep track of all the updates. Like a way so that whenever an update is done, it first copy/store the full master / childs data and then apply the update to the main DB.

Please guide me the BEST way to achieve this ? What is best option ?

  1. Just have a couple of update history tables and keep the data in Row / Columns ?

  2. Keep the data in XML ?

  3. Keep the data in JSON ?

Please guide !

Regards
ZH

That seems like the best bet.