What is process chain and how you used it? | SAP BI Interview Questions

A) Process chains are tool available in BW for Automation of upload of master data and transaction data while taking care of dependency between each processes.
B) In one of our scenario we wanted to upload wholesale price infoobject which will have wholesale price for all the material. Then we wanted to load transaction data. While loading transaction data to populate wholesale price, there was a look up in the update rule on this InfoObject masterdata table. This dependency of first uploading masterdata and then uploading transaction data was done through the process chain.