Backdrop: In the interest of using a practical example as a baseline for understanding let us assume that you are using an Enterprise Portal Setup which incorporates a lot of information with Knowledge Management (KM) repositories.
Storage Purposes – What is a CM Repository Manager ?
- A CM repository is used as the main repository for storing documents and folders that are managed by CM.
Throughout your review of the various material and options available you come across the three different modes in association to KM-CM.
- DB Mode
- DBFS Mode
- FSDB Mode
You want to export information from a database to a file-system is this possible?
Firstly these “modes” outlined above are feasible options for CM Repository mode choices and ordinarily are selected via preference by different customers depending on their setup and landscape. You may on some occasions see this “modes” labelled as “persistence modes” as this is another associated term.
Now back to question: Q: Can you export all information from a DB to File System?
A: In short the answer to this query is yes that this is indeed a feasible option and can be achieved via a transport package. Although from a high level perspective I would encourage diligence and to ensure that essential information is backed up as a general guidance rule of thumb.
In order to aid you in the transport and export you can make use of the following guidance documentation which provides a comprehensive and information overview:
- Exporting KM Content : https://help.sap.com/saphelp_nw70/helpdata/EN/46/77da3bb8036ef0e10000000a1553f6/frameset.htm
- Transporting KM Content : https://help.sap.com/saphelp_nw73/helpdata/en/49/b4dfbadcfc6bf9e10000000a421937/frameset.htm
DB VS DBFS VS FSDB
Let us work through the different modes and summarize what each are below (you may already be aware of the following based upon your previous analysis).
1: DB Mode: All data (documents, folders, and metadata) is stored in the database. If there is a large number of write requests in your CM usage scenario, set up the CM repository in database mode. Since all documents are stored in the database, this avoids unintentional external manipulation of the data. Another advantage of storing all data in the database is that the procedure for data backup and restore is easy since only the database needs to be backed up.
2: DBFS Mode: Metadata and folders are stored in the database, but documents are stored in the file system. This mode is faster than the database mode if you have large documents since there is no database data streaming. This mode also enables the size of the database to be controlled more easily since documents are stored in the file system. The documents and metadata are stored in different places, so you have to take into account both the database and the file system and synchronize them both when backing up and restoring data.
3: FSDB Mode: Folders and documents are stored in the file system, but metadata is stored in the database. In this mode, the file system is predominant. File systems are not transactional, so this mode has restrictions and affects performance. If read and write operations take place for one document in the file system at the same time, these operations have to be coordinated by the repository manager. This happens by recording both write accesses and read accesses in the database. This affects performance.