The delta queue is a data store in the source system into which data records are automatically written using an update process in the source system (such as with FI documents) or using extraction using a function module after a data request from the BW (such as LIS extraction prior to BW 2.0).
With a delta request, the data records are transferred from the Scheduler into BW.
The data is stored in compressed form in the delta queue. It can be requested from several BW systems. The delta queue is also repeat enabled. In other words, the delta queue stores data from the last extraction process. The repeat mode of the delta queue is specific to the target system.
With changes to the extract structure for a DataSource that took place between writing the data into the delta queue and reading of the queue data (for example with an upgrade), you can see from the data stored in the queue in which structure it was written to the delta queue. The queue monitor now contains fields that are now field that were not filled before and/or fields that were filled before but which are now unfilled.
You can use this function to check the delta queue.
The status symbol indicates whether or not update into a delta queue is activated for a DataSource. The delta queue is activated if the status symbol is green. In other words, it is filled with data records when an update or data request takes place from the BW. Prerequisite for a delta update is a successful execution of the delta method initialization in the BW Scheduler.
You can carry out the following activities:
· Display data records
· Display the current status of the delta-relevant field
· Delete the queue
· Delete queue data
1. To check how much data and what type of data is contained within the delta queue, select the delta queue and choose Display Data Records.
2. A dialog appears in which you can specify the data records display.
a. You can select the data packages whose data records you want to see.
b. You can display specific data records of the data package for display.
c. You can use the simulation of the extraction parameters to select how the data records are to be displayed.
3. To display the data records, choose Execute.
In the delta queue, you can display the current value of the delta-relevant field for DataSources that support generic deltas. Do so by choosing the button Detail in the Status column. The value displayed contains the largest value with reference to the delta-relevant field for the previous extraction. It is the lower limit for the next extraction.
If you select refresh,
· new activated delta queues are displayed,
· new data records written to the delta queue are taken into account
· and all data records that have since been deleted when the system read the data records, are not displayed.
To delete the data in a delta queue, select the delta queue and, from the context menu, choose Delete Data.
Deleting data from the delta queue does not require the delta method to be reinitialized to write DataSource data records into the delta queue.
Note that data that has yet to be read from the delta queue is also deleted. As a result, any existing delta update is invalidated. So, only use this function when you know what you are doing!
You can delete the entire queue via Queue → Delete Queue. You need to reinitialize the delta method before you can write data records for the associated DataSource into the delta queue.