A One-to-Many relationship between two entities indicates that one record in Entity A corresponds to multiple records in Entity B but one record in Entity B has only one associated record in Entity A.
Data integrity is the maintenance and consistency of data in a data store. Data can become inconsistent if changes are applied to fields in one table and not other tables.
What is EDI and what is an example of its usecase?
Electronic Data Interchange.
An example of its use would be a school wanting to automatically connect its information systems to the exam board so that candidate information and results are downloaded quickly on results day.