Two main Jobs
- Observer job (/1DH/OBSERVE_LOGTAB)
- Transfer job (/1DH/PUSH_CDS_DELTA) which's started by Observer job
If a record is changed, then database triggers write it into a master logging table /1DH/ML... (e.g./1DH/ML000000001). Afterwards, the Transfer job copies the records from master logging table to subscriber logging table /1DH/SL...(e.g./1DH/SL000000001). This job might already condense changes, e.g. two updates may lead to just one record in the subscriber logging table.
After the Observer job copies the logging table entries, the view reconstruction is executed. The view reconstruction selects the latest after images from the CDS view if there exists a corresponding key in at least one subscriber logging table. The result is written into unit of Operational Delta Queue (ODQ).
BW extraction reads from the ODQ. The records are written into the BW target (e.g. ADSO activation queue) in the same order as they were written into ODQ. If there are two records with the same key, then they still have the order as in ODQ. The DSO activation will keep this order as well.