In database we have a lot of data. Data is stored in tables (like in Excel). Each table has columns and rows and when they cross, then we will have cell of data, e.g. one data unit.
That particular data unit can be in following states:
- have value = NOT NULL value
- have no value = NULL value
In most cases values in integer cells have 0 as their value to indicate, that value isn't entered. But that's not completely true. What if 0 also means something. For such cases all such problematic cells should be normalized to represent one logic across all database.
That's what I'm proposing here.