Is there a way to add foreign constraints in a QLDB table?
Suppose I have two open tables, one with and another without, a primary key. Can I add a foreign key constraint referencing those with a primary key?
Does the same work with indexes? If I don't have any primary keys, but only indexes on the tables, can I add foreign key referencing these indexes?
There is no Primary Key or Foreign Key concept in QLDB at this time.
Document IDs are a closely related concept to Primary Keys in that each Document ID is a universally unique identifier.
To enforce Foreign Constraints on the application-level, you can SELECT before UPDATE or DELETE or DROP TABLE in a transaction to ensure the referential integrity of the Foreign Key.
