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Note: arcplan Information Services GmbH has been renamed after the merger with Longview and is now Longview Europe GmbH.
The local connection arrow enables the restriction of structures without limiting the data at the same time. This function has been existing for many years but is easily forgotten and completely unknown by many application architects and developers. Thus, this is a blog refresh or introduce this function.
Side Note Connection Arrow
By means of the tool Longview BI, queries can be generated without programming knowledge. By means of the so-called “connection arrow”, SQL or MDX codes are automatically generated. By drag and drop, the red connection arrows from the objects with database contents (characteristics and features) are just dragged onto the table.
Thus, the respective SQL statement is automatically generated; it can also be viewed (but not modified) in the database window and the specific database properties.
Special Use Case “Local Arrow”
Normally, the connection arrow limits the structure (feature) and the data in the same way. Let us say that we only want to view the countries which made a turnover in a selected quarter. However, we want to see the annual turnover at the same time.
In case of the classic restriction to quarter 3, we accordingly only see the turnover from Q3 – this can also be seen in the table on the left where only column Q3 is populated.
Thus, the restrictions from the connection arrows are passed through to the fact table.
If one selects Q2, France is filtered out of the query. Thus, France has not made any turnover in Q2. However, this does not answer the question. We are looking for the annual turnovers for the countries which made a turnover in Q2.
By means of the local arrow – identifiable by the purple color – only the structure is limited, not the fact table. This now shows the annual turnovers for 2014; however only for those countries which made a turnover in Q2. Now, the restriction affects “turnover >0 and Q2” only locally.
In the icon view, this can also be recognized by the small “stop signs”.
If you remove the table, which was only intended for illustration purposes, the resulting “annual turnover of the countries which made a turnover in Q2” now looks as follows.
Conclusion
The local connection arrow is a very powerful Longview BI function, which enables you to specifically treat the restriction to structures (features) and data differently within one query. This blog only showed a (construed) example for illustration. However, the application possibilities are extremely varied and numerous.
