Topic: Relationship between User and POS
Currently we have a field user in the table 0_audit_trail to store relationship between users and transactions.
In the future when transactions statistics for sales points is needed, developers can use user field in the table 0_audit_trial then join it with table 0_users to know which transaction is belong to which sales point.
This would cause wrong statistical problem if an user is moved to another sales points.
So it is necessary to have additional field pos_id in the table 0_audit_trail to fix the relationship between transaction and sales point