Are 0 and "" empty values?



In the context of this exercise, are 0 and "" empty values?


No, although logically, we may think that 0 represents some empty number or count, or that "" represents an empty text, which is not wrong, this does not mean they are empty values. In SQL tables, they are still considered to be values.

Instead, empty values in SQL would be represented with NULL, which means the absence of any value.