Unbelievable: Misinformation about The Dreaded Nines
By E.L. Core, Westergaard (click through and read the links)
April 27, 1999
Computers are complicated. So, information about computers is complicated. And misinformation about computers is complicated and, unfortunately, widespread.
I have already written at length about the alleged "Nines Problem" -- that problems will occur when processing data for April 9, 1999, and September 9, 1999 -- in two articles: The Dreaded Nines: Will They Be So Bad? and More on The Dreaded Nines and Other Proverbial Dates. (If you are unfamiliar with this topic, I strongly urge you to read those articles if you want to continue reading here.) I also wrote about them briefly at the conclusion of NERC's April 9 Y2K Drill: What It Is, And What It Is Not.
But, on April 20, I came across a tortured mishmash of misinformation on the "Nines Problem" that I want to examine in detail. It is in the form of question-and-answer. My comments are interspersed between the quoted sections that follow.
"Question: Some questions from my employees concern the date 9-9-99. Is there any concern for this date rolling over to all zeroes on systems? -- John"That question, in one form or another, is unfortunately quite common. As I have pointed out, 4-9-99 and 9-9-99 have been Y2K Red Herrings: "In one way or another, Y2K Alarmists have trumpeted those days as harbingers of the computer problems to come in 2000. Though each day, in its own way, may have relatively minor data-processing problems, their connection with Y2K is tenuous" (Don't Chase the Y2K Red Herrings).
"Answer: Sept. 9, 1999, is one of two dates thought to be susceptible to what is known as the 'Nines Problem.' When programmers writing applications want to signify an 'end-of-file' or 'end-of-process' command -- in other words, a condition that tells the computer 'if you see this date, you can stop' -- some used a date with four nines in a row, or '9999'...."The "nines" situation posited here does not involve merely four nines in a row as a trigger, but the appropriate number of nines in a row. If the data field in question allowed a maximum of three digits -- for current age, say -- then three nines would be the trigger (but only if the software was programmed accordingly). In a six-digit date field, then, the appropriate number of nines would be six, not four; in a five-digit date field, it would be five nines in a row.
"April 9, which recently passed without any errors making their way into the public eye, is the 99th day of the year. If a programmer used the Julian calendar -- which most folks stopped using when Pope Gregory introduced his innovations about 400 years ago -- there is the possibility that they could inadvertently trigger the end-of-file process."
My jaw dropped when I first read that paragraph. When programmers speak of Julian dates, they are not talking about the Julian calendar, but about a certain format in which dates are sometimes stored. (I have explained this format in The Dreaded Nines.) I have no idea why dates stored in that fashion are called Julian dates, but it apparently comes from IBM usage. Dr. J. R. Stockton has called it "a most unfortunate piece of nomenclature"; see his discussion of Our Calendars. The question-and-answer author explains storage of Julian dates correctly -- well, almost -- in the next paragraph.
"The Julian calendar would produce a '9999' date only if it was misformatted DDDYY, which would be '09999' on April 9. Correctly formatted (YYDDD), however, April 9 would appear as '99099'...."Storing a Julian date in "DDDYY" format is not a misformatting. Sometimes, it is not only legitimate but advantageous to keep Julian dates in that fashion, such as for a report that compares sales on a given date with sales on the same date in the previous year.
"In the Gregorian calendar, Sept. 9 is '990909,' not '9999.' No matter how badly mangled the Gregorian date format, it never produces '9999'...."September 9, 1999, is "990909" ("YYMMDD" format) or "090999" ("DDMMYY" format). Julian calendar, Gregorian calendar, no matter.
I shudder. True, there were no reports of major (any?) data-processing problems associated with April 9, 1999. But the explanation given here is just nonsense. As I explained above, storing a Julian date as "DDDYY" (which would make "09999" the Julian date of April 9, 1999) is not a mistake. Nor is the posited trigger a series of four nines: it is a series of all nines, and "09999" is not all nines."Presumably, if programmers decided to use a Julian calendar, they would be aware of the potential problem with the string of four nines when selecting an end-of-file command. Given the total absence of reports of major system errors on April 9, almost all programmers did avoid the series of mistakes that would have caused a problem."
"For the problem to kick in on Sept. 9, programmers would have had to make even more mistakes while writing their software -- they would have had to misformat the date in a way that defies logic."As if programmers are incapable of defying logic.
Seriously, I have already explained at length in More on The Dreaded Nines that data-processing problems may be associated with September 9, 1999 -- but not primarily because programmers have coded the software poorly (though that may be true in some cases) nor for other technical reasons which are not out of the question. Rather, because users have decided on their own to pick certain dates and attach special meanings to them -- one of those dates being September 9, 1999.
"The Nines Problem is almost totally a myth, except for misformatted Julian dates. And that critical date has already passed."Hardly. Indeed, as I explained in More on The Dreaded Nines, the argument for data-processing problems associated with September 9, 1999, has always been much better than that for April 9, 1999. Not that I'm predicting major problems for 9/9/1999, mind you: I am certainly not doing that. I'm just pointing out that the possibility exists, however unlikely.
It would have been bad enough had such a question-and-answer article -- such a mishmash of inaccuracies and outright errors -- come from, say, a pastor trying to explain the "Nines Problem" to the readers of his newsletter. Or from the director of a non-profit organization trying to explain it to his staff. Or from a journalist trying to explain it to the readers of a small-town newspaper. It would have been bad enough -- but excusable. After all, computers are complicated.
What would you say, though, if you knew that it came, not from a reporter nor from a bureaucrat nor from a clergyman, but from the "editorial director of Ziff-Davis' ZDY2K Web site and president of Internet/Media Strategies Inc., a Lakewood, Wash.-based consulting company" in an article "Special to ABCNEWS.com"?
Here it is, folks: No Revolution No. 9: Julian or Gregorian, Calendars Avoid 9999.
Yes, what would you say? The first word that came to my mind was "appalling". A week later it's still the word that comes to my mind.
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