Levels of locks
Objects:
- only locked when user opens them in property dialogues
- all properties are locked at the same time (object is greyed)
Graphs:
- obtain locks for both representational / conceptual graph
- if some of these fail not all actions are possible and mostly editing of conceptual objects possible (if have locks)
Projects:
- most difficult to manage the collection of graphs (of a project)
- usually locks have to be defined for all graphs with which the user wants to work with
Lock for metatypes
- repository exclusive; repository; project level
- also all instances are locked at the same time