Discovering data discrepancy issues
One of the main purposes of BI is creating reporting for the decision-making process. But what if the report produces the wrong data? We should find the reason and fix it. In order to do this, the best way is to copy the SQL statement in the SQL client and start to troubleshoot it.
Tip
Using VLDB settings, we can change the behavior of SQL generation in order to better understand the flow of data and easily troubleshoot it. For example, we can use sub-queries instead of temporary tables, and so on.
In addition, it is important to have the right numbers in order to know what to expect from numbers.
For example, we have the following report:
It is obvious that Order Quantity isn't aggregated. In order to understand why, we should look at SQL:
select a12.SALESREASONNAME SALESREASONNAME,
a13.COLOR COLOR,
sum(a11.ORDERQUANTITY) WJXBFS1
from EDW.FACTRESELLERSALES a11
cross join EDW.DIMSALESREASON a12
join EDW...