Comment by jerf
6 years ago
I doubt that. Normal people do not tend to use the word NULL at all.
What this usually is is the result of systems that talk to systems that talk to systems that talk to systems, all in different legacy formats never written to be interchange formats. One system has true SQL NULLs, the next system down the chain only accepts strings for that field, NULL gets written as the most sensible string, and then from that point on all downstream systems can't tell the difference between the original system having had an SQL NULL or having had the string NULL.
Maybe NULL is the default value if you don't enter anything
Did you read the article? It literally says people at a private citation outfit put NULL in the license plate field when there is no number available.
And I still expect my story is more accurate, with theirs being a reasonable expectation of what you'd get when some techie tells their manager what happened, who tells their manager, who tells the reporter.
To be clear, I'm not denying that what you say is literally true, just that by the time I'm done filtering that particular fact through my personal belief network and personal experiences, I still end up saying that my story is more likely. It's true enough that they put a "NULL" in, it's just that the way the private firm does that is most likely that the field agents leave it blank, some software somewhere puts a NULL in some database, and the report that comes out for the enforcing authority has NULL in it. For a reporter, it's not a false statement, it's just not all the technical details.
With this story, the responsibility ends up distributed in a very plausible manner I've seen many times over; HN readers could fill in a dozens of similar stories no problem. It's a problem characteristic of these sorts of systems and the way they tend to communicate with each other.
People use the word NULL and in all caps as well, in particular in bureaucratic processes like those you would encounter at the DMV.
NULL & VOID, etc.
It is entirely reasonable that the system would not accept an empty string for the plate so the process folks worked around that by instructing all employees to write NULL if they couldn't read the plate.
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As per HN guidelines, please don't ask or insinuate that someone's not read the article, instead just quote the relevant part.