Hi Apostolis, There is no requirement to definitely use multihash. The pointer to it in the "further info" section was just to show one way of handling different hashes. Thinking about it, even using it would not be enough, since, for example, it doesn't support SWHIDs (a very nice identifier to have). However, there is a requirement to handle and keep multiple hashes. I think I've replied to a similar question a few days ago, describing the steps that the user has to take in the case where only one hash is stored and why this is not desirable. On Thu, Apr 1, 2021, at 22:05, ΑΠΟΣΤΟΛΗΣ ΔΗΜΟΣΘΕΝΗΣ wrote: > Hello mentors, > > In the brief explanation of the project, it is said that it will be > used multihash. I have a question about that. Why use multihash instead > of a determinate hash function? > > As you said in a previous email, we should have for example 1 billion > files into the database. However, if we store multiple hashes for each > file into the database, then we should reach the memory limit of the > hard drive without storing 1 billion files which is our goal, and also > the time response of the program should be increased. > > Furthermore, is there a specific reason to search "if there is a file A > into the database encoded with the hash function B or C or D or E, ..." > instead of "is there a file A into the database"? > If a user wants to be sure about the existence or not of a file into > the database, then he would run the query to the database for all the > hash functions, consuming more time. > > Moreover, supposing that a simple user wants to check if a file exists > or not in the database and he doesn't know anything about hash > functions, etc. > The only thing he can do is to choose the file and parse it in the > input of the program. After that, the inner mechanism is a black box > for him because he only wants to see the result (the file exists / not > exists in the database). > Differently, if a user must have to choose a hash function, this factor > would make the app for him more difficult to use. > > Should I feel free to propose that there is no need to use multihash? > > Thanks in advance > Apostolis Demosthenes > > ---- > Λαμβάνετε αυτό το μήνυμα απο την λίστα: Λίστα αλληλογραφίας και > συζητήσεων που απευθύνεται σε φοιτητές developers \& mentors έργων του > Google Summer of Code - A discussion list for student developers and > mentors of Google Summer of Code projects., > https://lists.ellak.gr/gsoc-developers/listinfo.html > Μπορείτε να απεγγραφείτε από τη λίστα στέλνοντας κενό μήνυμα ηλ. > ταχυδρομείου στη διεύθυνση <gsoc-developers+unsubscribe [ at ] ellak [ dot ] gr > <mailto:gsoc-developers%2Bunsubscribe%40ellak.gr>>. > -- -- zvr -
---- Λαμβάνετε αυτό το μήνυμα απο την λίστα: Λίστα αλληλογραφίας και συζητήσεων που απευθύνεται σε φοιτητές developers \& mentors έργων του Google Summer of Code - A discussion list for student developers and mentors of Google Summer of Code projects., https://lists.ellak.gr/gsoc-developers/listinfo.html Μπορείτε να απεγγραφείτε από τη λίστα στέλνοντας κενό μήνυμα ηλ. ταχυδρομείου στη διεύθυνση <gsoc-developers+unsubscribe [ at ] ellak [ dot ] gr>.