back to article Learn to code site loses student work due to index bug

Learn-to-code site is apologising to its students after being caught by a database table maxing out, and dropping progress for an unknown number of participants. In its mea-culpa blog post, the group says it was burned by a database table with a 32-bit index. >“The way we store student coding activity is in a table …

  1. JeffyPoooh Silver badge

    That's very funny...

    See title.

    1. Anonymous Coward
      Anonymous Coward

      Re: That's very funny...

      It's pretty basic coding, isn't it?

      Still, they had backups.

      1. Wensleydale Cheese

        Re: That's very funny...

        I was preparing a wisecrack until I got to the bit where they'd only lost an hour's worth of work.

        Not bad at all in the grand scheme of things.

  2. Blofeld's Cat


    "Learn-to-code site is apologising to its students ..."

    At least they didn't say that "lessons had been learned" in their blog post ...

    1. Adam 1 Silver badge

      Re: Hmm...

      Isn't the standard to claim "No credit card information was accessed"?

  3. Simone

    Oh dear... "there's an hour of your life that you won't get back"

    To (mis-)quote a comedian (sorry forgotten his name)

    "unless you have a way of defeating the linear nature of time, you won't get back EVERY hour of your life"

    1. PeteA

      You wont't get ANY of them back, not just EVERY hour.

      1. Adam 1 Silver badge

        It's not just hours either. I'm not even going to get the 30 seconds back that it took me to write this comment.

  4. ST Silver badge

    Let's try again, then ...

    ... with 33 bits this time.

  5. RIBrsiq

    "Show, don't tell"...?

  6. Neil Barnes Silver badge

    It's always good to repeat previous instruction

    That's how we learn

  7. baconlt


    Sounds like a fencepost error.

    As in - the guy who coded that site will be working at his new job digging fenceposts.

    ... hah!

  8. Tom 38 Silver badge

    if you were working on “CS Principles and CS Discoveries:” courses, the outage means there's an hour of your life that you won't get back.

    Well, assuming the lesson is any good, its not a wasted hour, its an hour you spent learning things. If re-doing the things you learnt in that hour takes you another hour again, you probably didn't learn it that well and the extra look should be helpful.

  9. hatti

    Coding homework excuses

    1. I left it on the bus.

    2. The dog ate my code.

    3. The table where I saved my homework was maxed.

  10. Anonymous Coward

    4294967296 primary keys ought to be enough for anybody.

  11. Pseudonymous Clown Art


    That is all.

  12. Stevie Silver badge


    We used to get this sort of problem sometimes with new DBAs working with Unisys' CODASYL DMS 1100 databse tech. The 36 bit db key word is chopped to include dataset #, page #, and slot #. A DBA had to keep the page size and number of pages front and center during design spec or data could be stored that couldn't be retrieved. Our local term for it was 'bit out'.

  13. thomn8r

    1. Adam 1 Silver badge

      Don't understand the relevance of that sorry. The bug here is simply the wrong choice of data type meant all available values were exhausted. (Hint, for 64 bit fields that won't happen until after the heat death of the sun).

      The xkcd comic refers to the common mistake (let me guess, it is still OWASP top error) of not using parametrised queries and so allow a user not just to provide data, but additionally instructions.

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Biting the hand that feeds IT © 1998–2019