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...
Good point. However, approaching this problem from “YAGNI” point of view is a bit misleading, I think. If you are not going to need the timestamp, you shouldn’t add it to your code base.
In my opinion, hastiness is the culprit. When a property appears to be a binary one, we jump to the conclusion to use a boolean way too quickly. We should instead stop and ask ourselves if we are really dealing with a situation that can be reduced to a single bit. The point raised by the article is a good example: you may want to record the state change as timestamp. Moreover, in a lot of the cases, the answer is not even binary. The values for
is_publishedmay be, “Yes”, “No” or “I don’t know” (and then we will be too quick to assignnullto “I don’t know”). Underlying problem is that we don’t spend enough time when modeling our problems. And this is a sure way of accumulating technical debt.I think this timestamp-as-a-boolean is a good idea if the field is always going to be interpreted as either True or False and nothing more. If the field in question allows for a 3rd (uncertain) value, then using a timestamp would be extremely confusing.
I don’t agree it was a good point. It sounds like the blog author missed a requirement a few times, and after getting repeatedly burned in the requirements gathering stage he now overcompensates previous failing with I’ll advised usages of timestamps instead of booleans.
YAGNI is always true. Always. The author’s point, even when timestamps end up being required, are moot.
Also, if state changes are required them you don’t tack on a timestamp to a row. You instead track events, including switching stuff on and off.
I feel this blog post is bad advise fueled by trauma.