DBFieldDef :: get_create - Not allow creating new instances

This option allows suppressing the creation of new instances. One may still associate existing instances to the collection, but one cannot create new instances for the collection.

By default, the option is set. The option can be switched off (NO_CREATE option) for not owning reference collections. Usually, this makes sense only in connection with a defined base collection. When one of the base collections (in a hierarchy) is marked as NO_CREATE, derived collections are NO_CREATE by default.

For references marked as transient, the option defines the difference between transient and virtual or temporary collection. As long as create is true (default), a temporary collection will be created at run-time. When create is set to false, the collection will be opened as virtual (no index defined) or transient (at least one index definition) collection.

When the function is called with an invalid property definition, it throws an exception.