How can I do second dimension for the dimension, where we have comma delimited expression?
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We can use the property FullName as an example. Some values for this may be "Gevorg,Arutunyan" or "Steiwer,Peter". You can make a dimension with a source expression using $piece to extract the Last name or the First name. In this case, you may want a single dimension with 2 levels. The first level is "Last Name" that uses the expression: $piece(%source.FullName,",",1). The second level can be called "FirstName" and it can use the expression: $piece(%source.FullName,",",2).