Recognises rolled-down subtypes losing supertype constraints

Mida see tähendab

One table per subtype and none for the supertype. Uniqueness across subtypes cannot be declared, nothing stops one instance appearing in two subtype tables, and a relationship to the supertype has no single table to reference, so it becomes a polymorphic association (logical row 22).

Kuidas seda hinnatakse

Flags the deficient case and passes the acceptable one. Deficient: `person` and `organisation`, no `party`; `account_holder.party_id` cannot have a foreign key; nothing stops one id being used in both tables Acceptable: A `party` table with the shared key; `person` and `organisation` keyed by `party_id` with an FK to it; exclusivity enforced by carrying the discriminator into each subtype's key, or by a DQ rule

Tugineb

Recognises undeclared subtype constraintsK-519 · Oskus
Explains the implementation options for subtypesK-652 · Teadmine

Vajalik

Puudub