Kwok,
Could you advise what is the usage for these three fields under the "MRP 3" tab of the Material Master ?
I hope you have not failed to heed expert Jürgen's advice about convening a team of people to manage the archive process.
I am going to assume that you have done so, but the users on the team were unable to answer the question you just asked. My advice is that archiving must never be done by IT in isolation. I promise you that you will regret this if you try.
Planning Material and the related fields are used in two Planning strategies. The field in the Material Master is used to establish the linkage between a Finished Goods material and a Planning Material. For more info about Planning materials, read SAP help about Planning Strategies 60 and 63 for a start.
Planning with a Planning Material (60) - Demand Management (PP-MP-DEM) - SAP Library
Planning w/ a Planning Material and w/o MTO (63) - Demand Management (PP-MP-DEM) - SAP Library
Best Regards,
DB49