When data is imported into a table, and a column doesn't have any values. it is imported as NULL. Within databases, a NULL value signifies that the value is unknown. It does not indicate a value of 0. This article will go over different scenarios to explain how Sisense performs calculations that involve NULL values.
When you SUM values that are NULL, Sisense finds unknown information, rather than 0. This is an important distinction to have, because the sets [1,-1] and [NULL,NULL] should have different results when you aggregate them. 1+(-1)=0. Unknown+Unknown=Unknown.
SUM(NULL) + 1 = ‘No Results’
This one could be interpreted as unknown value + 1=unknown. You could think of this in algebra terms, where SUM(NULL)+1 is equivalent to x+1. There are infinite possible values for that equation, since x is an unknown variable. Unknown+1 is still unknown.