Assuming that there are multiple parties on the private blockchain, few general questions on the private blockchain usage:
Can Personally identifiable information (PII) data be stored on blockchain? does it fall under good architecture?
Lets say Party A (Entity) created a some data for one of its user U1 on the block chain. Around a week later, Party B just want to check if there exists anything on that blockchain for the same user U1 on the blockchain. Can Party B query on the blockchain on whether any Party created entry for U1?
My understanding is that no one else can read/verify anything on the blockchain for the entry that was created by another Party. Is that correct? If so, if I have the need to do the lookup on the blockchain, how can Party B do the lookup.