When do you need ArcSDE?
There are many benefits to using an ArcSDE geodatabase, but the main reason you would need ArcSDE is to take advantage of data scalability and the version-based multiuser editing environment.
Where File and Personal geodatabases are mainly single-user databases, ArcSDE offers a geodatabase that can be edited and used simultaneously by many users. Multiuser editing is achieved through the versioning framework. Versioning allows for long transactions which are key to many GIS workflows.
Following are some additional workflows that can be implemented using ArcSDE and versioning:
- Multiple projects with sub projects—A central geodatabase can distribute data for working with separate projects, some of which may be parent to their own sub-projects.
- Historical archives—Track changes to the geodatabase by maintaining a historical archive. The archive can later be queried to see how features looked at a specific time, or how they have changed over a time period.
- SQL access to GIS data through third-party applications—Enhance communication between the geodatabase and third-party applications by using the DBMS's native Structured Query Language (SQL) to access tabular data managed by the geodatabase.
- Mobile editors / Disconnected editing— Checking out replicated data to be edited in the field and then later connecting back to the network and checking the updated data back into the geodatabase.
- Loosely coupled replication across different DBMSes—Replicas can be distributed and their updates synchronized across offices even though each office may be using different DBMS platforms to store their data.
- Contractors—Share data with contractors by providing them with their own replica or version of specific datasets.
- Production / Publication systems —Some systems require support for editors and users with read-only access. The load can be divided with editors working on a production geodatabase that periodically sends updates to a published geodatabase with public access for users.
- Modeling scenarios—Separate versions of your data can be used as modeling tools to visualize scenarios such as natural disaster predictions or population growth.