SDB_Reference - References

References are used to describe any sort of reference collections. Thus, the reference definition is the base for defining local collections (references or relationships) as well as extents.

References can be defined as persistent collection, temporary collection (for extents, only) transient collection or transient reference.

Depending on the type of the reference, it is filled automatically, on demand or by the application program (context function).

References refer to persistent collection by default, when being defined as a property of a persistent instance or as extent. For persistent references, the transient option must be switched off. Persistent collections never have a source definition.

Collections defined as property (reference or relationship) of temporary or transient instances are, by default, transient or temporary, i.e. transient is supposed to be set to true.

Settings:

• transient: off
• source: none

Persistent collections are filled when reading the owning instance or opening an extent. No special user action is required.