Since the collection, which is mapped by the return variable (mappedBy) of the referenced objects, knows its type, the identifying column of the foreign key is sufficient, without having to use the discrimination column.

@startuml

class Library {
    -Long id
    -Set<Book> books
    +void setId(Long)
    +Long getId()
    +Set<Book> getBooks()
    +void setBooks(Set<Book>)
}

class Book {
    -Long id
    -Store store
    +void setId(Long)
    +Long getId()
    +Store getStore()
    +void setStore(Store)
}

interface Store {
}

Library --|> Store : implements
Library "1" -- "*" Book : contains

@enduml

…UMN_ROLE='roleName'") allows distinguishing instances belonging to the collection

…cate to be added to match the @SQLRestriction("COLUMN_ROLE='roleName'"), so that the collection loads only the elements that belong to it.

…minator column was missing. Shame on me.