So if i want to search and answer whether this file has been already seen i cannot just check if its sha-1 is available , because it might not be stored and maybe its sha-2 is stored. This will lead to counting and searching for all the allowed hash functions? Στις Τετ, 31 Μαρ 2021 στις 4:39 μ.μ., ο/η Alexios Zavras <zvr+eellak [ at ] zvr [ dot ] gr> έγραψε: > OK, yes, you are correct that there might be > a number of hashes for each file. > So the database may include: > - sha1(file1) == 0x1234... > - sha1(file2) == 0x5678... > - sha2(file2) == 0xABCD... > > Is your question how are these queried? > > > On Wed, Mar 31, 2021, at 09:41, Nikolaos Sokos wrote: > > Lets say we have a database that stores multiple hash values (for > > example sha1 , sha2-256) with multihash representation as you > > suggested. "For each file, a number of distinct hashes" this is where > > my question comes, for every file we must have the same hash functions > > and the corresponding hash values or can for example : File1 --> sha1 > > --> hash value-1 that is stored on database . File2 --> sha1 -->hash > > value2-1 & File2 --> sha2-256 --> hash value 2.2 and both stored . If > > we use multihash we can easily find out which hash function we use but > > when we try to search if a file has been seen again we dont know that > > hash value exists and we have to check for every allowed hash function. > > I hope this helps . > > Thanks for your immediate response, > > Nikos > > > > Στις Τετ, 31 Μαρ 2021 στις 10:19 π.μ., ο/η Alexios Zavras > > <zvr+eellak [ at ] zvr [ dot ] gr <mailto:zvr%2Beellak [ at ] zvr [ dot ] gr>> έγραψε: > > > Yes, of course there will be a database. > > > Maybe I misunderstood your initial question > > > and answered something different... > > > I thought you were asking about how to ensure > > > the integrity of "our" database if we were allowing > > > users to "upload" hashes. > > > > > > Can you repeat (using other words) your question, please -- > > > or give an example so that I can better understand? > > > > > > On Wed, Mar 31, 2021, at 08:40, Nikolaos Sokos wrote: > > > > Thank you for the clarification but I am still a bit lost. Even if > we > > > > don't have to collect data, shouldn't we know or create Database > > > > structure? So we can maintain and search it faster? > > > > > > > > Στις Τετ, 31 Μαρ 2021 στις 8:36 π.μ., ο/η Alexios Zavras > > > > <zvr+eellak [ at ] zvr [ dot ] gr <mailto:zvr%2Beellak [ at ] zvr [ dot ] gr> <mailto: > zvr%2Beellak [ at ] zvr [ dot ] gr <mailto:zvr%252Beellak [ at ] zvr [ dot ] gr>>> έγραψε: > > > > > HI Nikos, thanks for your interest. > > > > > > > > > > The goal of the project is to create software > > > > > that creates, maintains, and searches a database of hashes. > > > > > It is not to offer a service nor to collect data of such a > database. > > > > > > > > > > Therefore there is no "our Database" where a user > > > > > might "wants a file hash to be stored into", > > > > > no files to be uploaded or anything like that. > > > > > > > > > > I hope it's a little clearer now. > > > > > > > > > > On Wed, Mar 31, 2021, at 03:27, Nikolaos Sokos wrote: > > > > > > Greetings, > > > > > > My name is Nikolaos Sokos and I am currently studying Computer > > > > > > Engineering and Informatics at Patras,Greece.I have a question > about > > > > > > the project : Lets say a user wants a file hash to be stored > into our > > > > > > Database should every hash value accepted be calculated and > saved or > > > > > > can the user choose the type of hashing. The main problem if the > user > > > > > > can choose is that when for example the same file is uploaded > but with > > > > > > another hashing we have to recalculate every acceptable hash and > check > > > > > > if it is already stored (or look for a better solution?) What > does the > > > > > > project suggest ? Should we save every single hash or find a way > to > > > > > > check if different hash value is stored? > > > > > > I really hope I made my point clear, > > > > > > Thanks for your time , > > > > > > Nikos > > > > > > > > > > > > ---- > > > > > > 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 [ at ] ellak [ dot ] gr> <mailto: > gsoc-developers%2Bunsubscribe [ at ] ellak [ dot ] gr <mailto: > gsoc-developers%252Bunsubscribe [ at ] ellak [ dot ] gr>> > > > > > > <mailto:gsoc-developers%2Bunsubscribe%40ellak.gr <mailto: > gsoc-developers%252Bunsubscribe%2540ellak.gr> <mailto: > gsoc-developers%252Bunsubscribe%2540ellak.gr <mailto: > gsoc-developers%25252Bunsubscribe%252540ellak.gr>>>>. > > > > > > > > > > > > > > > > -- > > > > > -- zvr - > > > > > > -- > > > -- zvr - > > -- > -- zvr - >
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