In contrast to DatabaseIsRepresenterOfFacts, a database (DB) is a representer of complete b.s.

Businesses deal with lots of random b.s. every day.  
  b.s. in
  b.s. out
A database contains a lot of b.s. that may or may not be true.

A DB is a fuzzy b.s. storage device.  NULL is the perfect representation of b.s., so the database must have a NULL or it isn't a good database. 

A DB must not be restrictive or have constraints because b.s. is very fuzzy and doesn't fit particular categories.

A DB should allow unlimited value logic instead of two value logic. 

''It does. Just create an extra column for confidence. And then you can represent facts that include BS about your confidence.''

One option is to offer an opinion rating byte type column (on a scale of 0 to 255, please rate how confident are you that this row is complete b.s.). However the byte type makes it too restrictive, likely it should just be a blob or a string type so that you could put personal mumbling and commentary in the cell describing your hatred or love for the particular row in question.

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CategoryHumor