Re: a lesson in query writing and (maybe) a bug report

[Arthur Fuller]

I agree 110%. It is completely pointless to index a column with that amount
of NULLs. In practical fact I would go further: what is the point of a
NULLable column? I try to design my tables such that every column is NOT
NULL. In practice this is not realistic, but I try to adhere to this
principle whenever I can. For example, it's possible to add a new Hire while
not yet having determined which department s/he will work in, and hence
which manager s/he will report to, but typically I deal with such scenarios
by creating an "Undetermined" value in the corresponding lookup table.

Arthur