Fact tables in which data in columns data cannot be aggregated or calculations cann't be possibel for producing the expected results or known as non-additive facts.
# Additive: Additive facts are facts that can be summed up through all of the dimensions in the fact table. # Semi-Additive: Semi-additive facts are facts that can be summed up for some of the dimensions in the fact table but not the others. # Non-Additive: Non-additive facts are facts that cannot be summed up for any of the dimensions present in the fact table.
Basically all the measure can be summed up. These definations of additiive semi-additive and non-additive measures is based upon the requirements. If you want to sum up a measure for some dimensions but not for others then it become your semi-additive..and while creating a cube you take care of this thing.
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