In my 15+ years of web development, there are very few things I can say are unequivocally a good idea. It almost always does depend. Storing timestamps instead of booleans, however, is one of those things I can go out on a limb and say it doesn’t really depend all that much. You might as well timestamp it. There are pl...
Yeah, this feels like "premature optimization". When you design your applications and databases, it should reflect your understanding of the problem and how you solved it as best as possible. Using
DATETIMEOFFSET NULL
when you actually meanBIT NOT NULL
isn't saying what you mean. If you already understand that you have a boolean option and you think you might need a timestamp to track it, use 2 columns. Or an audit table. So sayeth the holy SRP.