Tech2know

Friends, if we talk about data then the term database and DBMS automatically comes in the mind. Well, of course because these are the  technologies that revolutionize the way data is stored and fetched. But it is a reality that no matter how good is your DBMS, there is always a limit of the data that can be stored at a time in database without degrading the performance in fetching the relevant data. If the volume of data grows beyond this limit then the performance degrades. So, what to do if the data volume starts affecting the performance.

The solution that comes in mind is to remove the unnecessary data from the database. Yes, it is. But we cannot delete business related data directly from the database because first it is important to check the completeness of the business transaction and legal requirements. For example, it is mandatory in some countries that financial data must remain accessible for 7 years.

Here comes archiving in the picture. Archiving is equivalent of deleting data from the database but with all application related checks which are necessary before removing data from the database.  Once archived, the data is stored in flat files called archive files and these can either be stored in storage system which is connected to production system(example an SAP R/3 system) or in a secondary storage devices like CDs, tapes. The data remain accessible to SAP financial transactions via connected storage system or a tape. Apart from accessibility of archived data, archiving saves storage space also by compressing the the data to a factor of 5 and then storing it in archive files.

In SAP R/3, archiving is performed via Archiving Objects. There are different archiving objects in SAP R/3 system depending on the data which they archive.

Below is the archiving procedure in SAP R/3 system :

1) Write phase

During this phase data is read from the database and then written to archive files. Of course, all application related checks on data are performed during the write phase only. If a data object passes all these checks then the data object is written to archive file.

2) Delete phase

This the phase in which data is read from the archive file and matching data is deleted from the database. Obviously because the data in the archive file has already passed all the application related checks during write phase and hence can be deleted from the database.

3) Storage

This is an optional step. In this step the created archive files can be stored in a storage system which is connected to an R/3 system. This step can be performed automatically(depends upon customizing settings on archiving object) or manually.

Is it mandatory to follow above sequence

In most of archiving configuration in SAP R/3, above three phases are followed in sequence. But, there is an option in customizing settings of archiving object which starts Storage phase before Delete Phase. I think that this option slows down Delete phase because in this scenario delete program, which reads archive file and delete matching data from database, has to read archive file from  storage system and not from the R/3 system itself.

Please share your thoughts through comments.

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Related posts:

1. SAP Archiving – Important Customizing for Archiving Object FI_DOCUMNT
2. SAP Archiving Objects
3. SAP Archiving – Archive Administration SARA
4. SAP Archiving – Archive Index ARIX_BKPF for Accounting Documents
5. SAP Archiving – Find Tables Included in Archiving Objects