(SP20) Activation of Data
In this part, activation of data in Data Store Object will be discussed. As the active table is only affected by activation, writer enhances only this functionality.
DSO Request Activation
Activation of request in Data Store object with Writer consists of 3 steps:
- Pre-Process phase – in this phase new records from a locked period are selected from the update table for currently activated request. Here The Maximum number of locked records that can be updated using NLS Writer, is set by using the settings parameter 'WRITER_ODSO_MAX_RECORDS'. This process uses OutBoard indexes to find the data within the OutBoard archive matching the same key as new data. Afterwards the process moves all needed data from the archive into an active table of Data Store object. When all records to be activated are found and correctly reloaded, the process will suppress the check for locked data so the activation can start.
- Standard SAP Activation – Standard activation process used by Data Store Object
- Post-Process phase – After successful activation of the data, the process will take the locked data from an active table of affected DSO and move this into the archive. There are three possibilities how the records are handled in this phase:
- Update – in case the records already existed and were changed by activation, post processing will find the existing records in archive and modify them with new ones from active table.
- Insert – in case these records are new, there is nothing to update and new package will be created within archiving request for these records. There is restriction for size of the package in settings, which describes the maximum number of records for package. In case that this size is reached, another package is created for the rest of the data.
- Delete – in case of the BW Delta Process: Update Mode (0RECORDMODE) is set to 'R' or 'D'; records are deleted during activation process. In Post-Process phase the keys of the deleted records stored, so the process also deletes the records from NLS archive. During this phase an internal table is used as a buffering table for storing the updated packages that should be moved back to archive. If the number of updated packages, stored in the internal table, reaches the maximum number of packages (parameter 'WRITER_MAX_BUFFERED_PACKAGES'), the packages are stored into a generated database table. This table is then deleted after the data is successfully updated in archive.
Note: If issue with authorization occurs, you'll be informed in displayed message. We recommend checking transactions SM37 and SLG1, where there will be further information about problem solving. One of known issues is case of loaded request, that couldn't be activated.
DSO Request Deletion
Follows a similar process to DSO Request Activation, however it differs during the pre-process phase, because the locked records are selected from the ChangeLog table.
SPO with DSO activation
On HANA database, do not process activation in parallel, but rather do it sequentially to preserve data consistency!
Reloading of archived Data
When the Writer moves archived data in an InfoCube and activated data in Data Store Object into the NLS archive, this data will be read or reloaded. SAP information generated from the moving of data, like the number of packages, number of records in package and request etc. are rebuilt . So in general the reloading of archiving request is the same with or without Writer, as the data is available. User just needs to go to archiving tab of InfoProvider in transaction RSA1 and then reload requests.
Writer has automatic reload functionality, too. At the beginning of a DTP load to cube / DSO activation, empty archiving requests are reloaded.