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As soon as it made the 1919=2019 mistake you know it's the ancient tale of 2 digit years being insufficient for dates. Wonder how systems determine if it should

by rtkwe 7y ago

As soon as it made the 1919=2019 mistake you know it's the ancient tale of 2 digit years being insufficient for dates. Wonder how systems determine if it should be 19XX or 20XX? Does it just default to the most recent year?

roywiggins 7y ago
They kicked the can 20 years in 1999: https://www.newscientist.com/article/2229238-a-lazy-fix-20-years-ago-means-the-y2k-bug-is-taking-down-computers-now/ https://www.newscientist.com/article/2229238-a-lazy-fix-20-y...
- rtkwe 7y ago
  Haha I should have known it would be even simpler than trying to estimate which date is reasonable. Interestingly Oracle just treats all XX as 20XX from my brief testing when doing to_date with 'YYMMDD' as the format.
  - trollied 7y ago
    This is how it works in Oracle: If you use the TO_DATE function with the YY datetime format element, then the year returned always has the same first 2 digits as the current year. If you use the RR datetime format element instead, then the century of the return value varies according to the specified two-digit year and the last two digits of the current year. That is: If the specified two-digit year is 00 to 49, then: * If the last two digits of the current year are 00 to 49, then the returned year has the same first two digits as the current year. * If the last two digits of the current year are 50 to 99, then the first 2 digits of the returned year are 1 greater than the first 2 digits of the current year. If the specified two-digit year is 50 to 99, then: * If the last two digits of the current year are 00 to 49, then the first 2 digits of the returned year are 1 less than the first 2 digits of the current year. * If the last two digits of the current year are 50 to 99, then the returned year has the same first two digits as the current year.
    - rtkwe 7y ago
      Interesting I've never had to dig into that, started working well after Y2K and the company I work at, as far as I see, properly converted any legacy XX years ages ago. Is the switch date for RR fixed? Seems like there will be some weird breakage around 2050 as random places that have been skating by on using RR for old 2 digit years will be in trouble.
- koboll 7y ago
  >WWE 2K20, a professional wrestling video game, also stopped working at midnight on 1 January 2020. Within 24 hours, the game’s developers, 2K, issued a downloadable fix. An almost poetic irony
  - rtkwe 7y ago
    I had heard that that was actually an ISO year issue. For example 2019-12-30 becomes 2020-12-30 if you mistakenly use IYYY-MM-DD instead of YYYY-MM-DD (which kind of makes sense IYYY shows up first in documentation).
verelo 7y ago
Having worked in the OCR world pretty much non stop for about a decade, i'd say its more just a case of there not being a lot of 101 yr olds, and there being a lot of 1 year olds; the system is likely over-optimized for switching the digits to 20 v's 19 as it's more probable that the individual is 1 than 101. Really, when the confidence is low, or the data seems exceptional, it should be flagged for a manual review.
- 6510 7y ago
  There are many more 101 year olds than 1 year olds doing their own administration.
  - verelo 7y ago
    I'm not sure what the user experience is, my assumption is that it could be the individual or a parent scanning this data, so unless it was attached to a parent profile before entering the data, it's hard to know who is doing the administration. Having said that, if your assumption was correct ("The person is doing their own administration"), i'd agree with you.
    - zenlot 7y ago
      It's not hard. In EU settlement scheme application you have to tick a box if you're applying for yourself or someone else is doing that for you.
      - verelo 7y ago
        That makes sense, thanks for the context! I've been through Canadian immigration processes (I'm from Australia), but have no idea how the UK/EU process works.
  - deleted 7y ago
    [deleted]
  - baddox 7y ago
    I bet not that many more.
jackcodes 7y ago
Storage is that cheap that I’m not far off using a BigDecimal for my years
kozziollek 7y ago
Recently I was fixing bug in some perl app, because since January 1st 2020, year 2070 is closer than 1970 and suddenly our dates were from the future.

by rtkwe 7y ago

roywiggins 7y ago

They kicked the can 20 years in 1999: https://www.newscientist.com/article/2229238-a-lazy-fix-20-years-ago-means-the-y2k-bug-is-taking-down-computers-now/ https://www.newscientist.com/article/2229238-a-lazy-fix-20-y...

rtkwe 7y ago
Haha I should have known it would be even simpler than trying to estimate which date is reasonable. Interestingly Oracle just treats all XX as 20XX from my brief testing when doing to_date with 'YYMMDD' as the format.
- trollied 7y ago
  This is how it works in Oracle: If you use the TO_DATE function with the YY datetime format element, then the year returned always has the same first 2 digits as the current year. If you use the RR datetime format element instead, then the century of the return value varies according to the specified two-digit year and the last two digits of the current year. That is: If the specified two-digit year is 00 to 49, then: * If the last two digits of the current year are 00 to 49, then the returned year has the same first two digits as the current year. * If the last two digits of the current year are 50 to 99, then the first 2 digits of the returned year are 1 greater than the first 2 digits of the current year. If the specified two-digit year is 50 to 99, then: * If the last two digits of the current year are 00 to 49, then the first 2 digits of the returned year are 1 less than the first 2 digits of the current year. * If the last two digits of the current year are 50 to 99, then the returned year has the same first two digits as the current year.
  - rtkwe 7y ago
    Interesting I've never had to dig into that, started working well after Y2K and the company I work at, as far as I see, properly converted any legacy XX years ages ago. Is the switch date for RR fixed? Seems like there will be some weird breakage around 2050 as random places that have been skating by on using RR for old 2 digit years will be in trouble.
koboll 7y ago
>WWE 2K20, a professional wrestling video game, also stopped working at midnight on 1 January 2020. Within 24 hours, the game’s developers, 2K, issued a downloadable fix. An almost poetic irony
- rtkwe 7y ago
  I had heard that that was actually an ISO year issue. For example 2019-12-30 becomes 2020-12-30 if you mistakenly use IYYY-MM-DD instead of YYYY-MM-DD (which kind of makes sense IYYY shows up first in documentation).

verelo 7y ago

Having worked in the OCR world pretty much non stop for about a decade, i'd say its more just a case of there not being a lot of 101 yr olds, and there being a lot of 1 year olds; the system is likely over-optimized for switching the digits to 20 v's 19 as it's more probable that the individual is 1 than 101. Really, when the confidence is low, or the data seems exceptional, it should be flagged for a manual review.

6510 7y ago
There are many more 101 year olds than 1 year olds doing their own administration.
- verelo 7y ago
  I'm not sure what the user experience is, my assumption is that it could be the individual or a parent scanning this data, so unless it was attached to a parent profile before entering the data, it's hard to know who is doing the administration. Having said that, if your assumption was correct ("The person is doing their own administration"), i'd agree with you.
  - zenlot 7y ago
    It's not hard. In EU settlement scheme application you have to tick a box if you're applying for yourself or someone else is doing that for you.
    - verelo 7y ago
      That makes sense, thanks for the context! I've been through Canadian immigration processes (I'm from Australia), but have no idea how the UK/EU process works.
- deleted 7y ago
  [deleted]
- baddox 7y ago
  I bet not that many more.

jackcodes 7y ago

Storage is that cheap that I’m not far off using a BigDecimal for my years

kozziollek 7y ago

Recently I was fixing bug in some perl app, because since January 1st 2020, year 2070 is closer than 1970 and suddenly our dates were from the future.