Performing Real-Time Indexing for DataSource-Based Connectors

Use

If you use SAP HANA or SAP BW Accelerator, real-time indexing means that data is available for close to real-time analysis. Real-time indexing for DataSource-based connectors can be performed both for DataSources for which the application writes the delta directly to the delta queue (push) and for DataSources for which the delta is only written to the delta queue when requested (pull).

Prerequisites

The DataSource must support real time.

Procedure

Start Real-Time Indexing

If you want to use real-time indexing for a DataSource-based connector, proceed as follows:

Select the connector in the Administration Cockpit and choose Actions Schedule Indexing .
To start real-time indexing, select the Start Immediately and Indexing in Real Time checkboxes and press OK.

More information about scheduling real-time indexing: Starting Indexing of Connectors

Result

Once real-time indexing has been set, a daemon process is scheduled in the delta queue (known as the ODQ daemon). If the daemon process is already scheduled, it adds the subscriptions in question to the process. A request is opened for the subscription. This request will stay open for at least 24 hours.

In the Delta Queue Monitor, the subscription and the request are displayed with the RT (object is in real-time mode) flag.
The ODQ daemon is a periodic background job that has the following tasks:
- Extraction
  
  The job checks whether a subscription running in real-time mode requires a pull, meaning that extraction has to be performed. If this is the case, the job writes the data to the delta queue. This is done using selection via a delta-specifying field, normally a time stamp.
- Notification
  
  The job checks for changes in the subscriber's queue and notifies the subscriber if any are found.
  
  Note
  Notifications are only sent if the subscriber type requires this, for example, subscriber type Search and Analysis.
In the default setting, the job is scheduled with a period of 15 minutes and a takt cycle of 15 seconds. This means that the background job is completed and a new one started every 15 minutes. The job checks in 15 second cycles whether extractions need to be performed and notifications sent to subscribers.
With the notification, the ODQ daemon starts the indexing job - if not started already - or makes the indexing job restart if previously interrupted.

More information about the indexing job: Controlling Real-Time Indexing
The indexing jobs reads the data from the delta queue and writes it to the SAP HANA database or to the BWA.

Monitor Real-Time Indexing

Monitor the ODQ Dämon and Requests in Real-Time Mode

In the Delta Queue Monitor (transaction ODQMON) you can monitor the ODQ daemon and requests in real-time mode:

To monitor requests, restrict the information displayed in the monitor to Only Real Time in the Request Selection field:
- Requests that are currently being processed by the daemon process are displayed with status .
- Requests that are not being processed by the daemon process any more and are now closed are displayed with status and are included in the delta queue reorganisation.
To monitor the ODQ daemon, choose Goto Real Time Daemon in the monitor.

More information: Monitoring and Scheduling Daemon Processes for Real-Time Processing

Monitor Indexing Job

In the Administration Cockpit, the Last Indexing column in the connector overview shows you when data was last written to the SAP HANA database or to BWA. By choosing Start of the navigation path System Settings Next navigation step Manage Indexing in Real Time End of the navigation path , you can monitor the indexing job.

More information: Controlling Real-Time Indexing

Stop Real-Time Indexing

To stop real-time indexing, proceed as follows:

Select the connector in the Administration Cockpit and choose Actions Schedule Indexing .
To stop real-time indexing, deselect the Indexing in Real Time checkbox, select the Start Immediately checkbox and press OK.