Using a HANA Reference Element in a Smart Data Streaming project

Beginner

15 min.

SAP HANA streaming analytics, SAP HANA studio, Tutorial, Beginner

Part 4 of 9. Add a HANA Reference element and using a Join operator to combine reference and streaming data.

You will learn

How to add a HANA Reference element to the project
How to join event streams to SAP HANA tables in order to enrich raw event data
How to filter and analyzing data based on context or historical information from HANA

Step 1
This is a continuation from part 3 of this tutorial group. Before proceeding, please make sure that "freezer_monitoring" project is opened and the project diagram is the active tab in HANA Studio. If not, go to File > Open File… to open the project. Navigate to the SAP HANA Administration Console perspective.

Open the Catalog for the HANA system in the HANA Systems view.

Open the “SYSTEM” schema and drag then drop the table MACHINE_REF onto the canvas.

Note: if you don’t see the tables you have created, try right clicking the schema and selecting Refresh. Make sure to use the same schema you create the table with before. In this case, you are using SYSTEM.

Select Reference, Inline and then click OK.

Change the name of the reference element to MACHINE_REF by clicking on the icon shown below.

Which table are you creating a reference to?
ACTIVITY_HIST
DASHBOARD
DENSTREAM_OUTPUT
MACHINE_REF
POWER_OUTAGES
Step 2
Click Join in the Palette and drop it onto the canvas.

Select the Connector tool. (Tip: press Shift key while performing the action. This will keep it selected for adding multiple connections)

First click on MACHINEDATA and then Join1 to connect them.

Now add a connection from MACHINE_REF to Join1.

Click Select in the Palette to release the Connector tool (or press ESC).

Rename Join1 to DEVICE_EVENTS and press Enter key.

Hover over the DEVICE_EVENTS shape so that the toolbar appears and then click the f(x) (Add Column Expression) icon shown below.

Click the Copy Columns from Input menu item to execute it. You can also press c.

Click Select All or you can also press Alt+s. Uncheck the 2nd MACHINEID field that is named MACHINE_REF.MACHINEID (we don’t want it twice) and then click OK.

Now set the join condition. Double-click on , MACHINE_REF.

When it prompts you to save the project, click Yes.

We want to join on MACHINEID. Select MACHINEID : string in each source column and then click Add. Once its been added click OK.