Slide 7 of 52
Notes:
Co-ordinating the editing of multiple concurrent users can be a difficult and time-consuming task. With traditional GIS the usual approach is for each user to make his/her own physical copy of the central version of a digital geographic database, requiring considerable space for the duplicates.
After making changes, these changes must then be merged back into the central version, along with everyone else's changes. However, there is generally very little support for comparing two users' versions of the same geographic coverage to determine the differences.
With an OO-GIS managing multiple users' long transactions, these issues are greatly reduced. This provides the 'check-in/check-out' semantics without the expense of actually copying unchanged data.
The GIS database can be stored on a single host computer, greatly reducing storage requirements. Each user sees a virtual copy, not a physical copy, of the central database.
OO-GIS administration tools support comparison of two versions of a given database, to report which geographic features have changed between them. The 'Local Integration' function represents the potential need for conflict resolution between multiple users' changes to the database.
