KB45517: Why are some metric values blank in documents using multiple datasets in MicroStrategy Analytics Enterprise 9.4.1

Introduction
Starting with Strategy Analytics Enterprise 9.4.1, report services documents can contain grids with objects coming from more than one dataset. This feature is documented in the following Strategy Knowledge Base document:
KB44944: Multiple datasets in a single grid/graph/widget object in Strategy Web 9.4 
 
Users can set the set the source of the grid to a particular dataset or choose no dataset (in which case, the Strategy engine will determine the best suited dataset)
The Strategy Analytical engine displays no data for metrics in ambiguous cases or when there is a conflict. Ambiguous cases can arise in cases where multiple datasets contain the same objects.  Examples based on the Strategy Tutorial project have been provided to explain this information.
Note: When the Strategy Analytical Engine cannot resolve the correct datatset as explained in the cases below, the data displayed for these will correspond to the value chosen for the missing object display under Project Configuration > Report definition > Null values > Missing Object Display. The default value for this blank.
 
Case1:
Multiple datasets have the same metric. Only one dataset does not contain this metric and this dataset is set as the source of the grid.
 
This case is explained with an example based on the Strategy Tutorial project.   

• Create the following objects:
  a. Dataset DS1 with the attribute 'Year' and metric 'Profit'.
  b. Dataset DS2 with the attribute 'Year' and metrics 'Profit', 'Revenue'.
  c. Dataset DS3 with the attribute 'Quarter' and metric 'Cost'.
  
• Create a document based on the above datasets and create a grid object on the document with the following objects: 'Year', 'Quarter', 'Profit'. Set the source of this grid to be the dataset 'DS3'.
• In the executed document, no data is displayed for the metric 'Profit' as shown below.
   
  

In the above example, the metric 'Profit' does not exist in the source dataset 'DS3' and exists in more than dataset which are in the document i.e., it exists in both 'DS1' and 'DS2'. Since the engine cannot just randomly pick one of the two available datasets, it chooses not to display any data for this metric. If users do not want such blank columns to be displayed, set the source dataset so that such ambiguity does not arise.
 
Case 2:
The same metric exists multiple times on the grid. For example, users can have a smart compound metric and a component metric of this compound smart metric on the grid in the document. The smart metric and the component metric are from different datasets.
 
This case is also explained with an example based on the Strategy Tutorial project. 

• Create the following objects:
  a. Dataset DS1 with attribute 'Year' and metric 'Profit'. 
  b. Dataset DS2 with attribute 'Year' and metrics 'Revenue', 'Profit', 'Profit Margin' (this is a compound smart metric calculated from metrics Revenue and Profit).
  
• Create a document based on the above datasets and create a grid object on the document with the following objects: 'Year', 'Revenue', 'Profit' and 'Profit Margin'. The source of this grid object is set to DS1.
• In the executed document, no data is displayed for the metric 'Profit Margin', as shown below.
   
  

In the above example, since the source of the dataset is set to 'DS1', the 'Profit' metric is sourced from this dataset and the metric 'Revenue' is sourced from the dataset 'DS2' (as this is the ONLY datatset with this metric). However, for the metric 'Profit Margin', the component metric 'Profit' exists on dataset 'DS1', so this becomes a conflict metric and is not displayed. If the source of the grid is changed to 'DS2', the data is displayed correctly as shown below.