When running cube processing and choosing to ignore key errors, there is an optional action for missing keys to ‘Convert to unknown’.
In other words, when we ignored the errors, the data belonging to those erroneous keys was not totally ignored. They were actually converted to an ‘Unknown’ category.
Now we just need to make this unknown category visible when we browse our data.
First we will open the Item dimension, because this was the dimension that was reported having dimension key errors. To view properties, right-click the dimension itself.
The property we are looking for is called the ‘UnknownMember’ property, and we want to change the value of this property to Visible.
The change of this property will have an effect when browsing the dimension and when browsing the cube. However, both need to be processed again before we can see any changes.
When you re-process a dimension or a cube or the entire Analysis Services project, you may experience that the browser does not reflect any of your changes. This is most often because the browser was already open during the re-processing, and you will need to re-connect to the database to see before you can see any changes.
Sometimes you will get a warning regarding the necessity to re-connect. But otherwise it is recommended re-connecting every time you re-process.
Now, when we browse the cube, we can see that indeed data that was otherwise lost is now related to the ‘Unknown’ category.