On Tue, Nov 17, 2009 at 3:37 PM, le_sacre <[email protected]> wrote: > It seems to me that what Samuel wants is not wholly at odds with SRS; > it would just require a complete reinvention of how Mnemosyne is > engineered. > > What Samuel has not seemed to grasp is that there are two classes of > information in the deck, and they are stored in the same file. One > class is the actual data that displays on the cards, the content. The > other is the learner's performance data for each card, including how > many times and when it's been reviewed, how difficult it is, etc. SRS > works by updating this performance data every time a card is reviewed, > to control when the card will next be scheduled. > > It seems to me that it's by no means strictly necessary for the > content data and performance data to occupy the same file. For a > school environment you could (theoretically) lock the content data, > while having a separate file that contains the performance data for > all the students, with each student being given a password that > enables the system to update only their performance data in this file > as the cards are reviewed. There would still be the same issue of the > danger of tampering, until some form of user login is implemented on > the computer(s) (on Macs this is easy to do--don't know about PCs), > but the teacher could make regular backups of both files. > > Of course, this would practically involve rewriting Mnemosyne from > scratch to achieve. But I don't think it's accurate to say SRS is in > general completely incompatible with what Samuel's requesting.
That's true, you could split up the data over multiple files. (You could also have each card be a file, or contain every card starting with the letter 'A' and so on.) But there's a good reason to have one file rather than many: besides being easier to write, easier to understand, easier to backup, a single file makes it easier to have *consistency*. (Notice that SQLite - which Mnemosyne 2.x will use - also uses a single file model.) If you have one file for grades and one for cards, imagine a power failure interrupts or any failure of any kind from a platter on the hard disk all the way up to the actual Mnemosyne running - what happens? Do you wind up with a card-file which has fewer cards than the grade-file specifies (perhaps you deleted or merged some)? Do you have a grade-file assuming a card-file with different contents? With one file, it's all or nothing. You lose all your work, or you save all your work; but you won't wind up with a database which is corrupt, incomplete, or contradictory. (Mnemosyne currently will add new questions before shutdown, but everything else gets written out in one batch to one file.) -- gwern -- You received this message because you are subscribed to the Google Groups "mnemosyne-proj-users" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/mnemosyne-proj-users?hl=.
