git - Hash collision in commits from all version control systems -


i read hash collision in git appears unlikely 2 different commits in git have same hash.

but commits not git? application working git,svn,hg - can assume there no different commits same hash?

for i'm trying deside how stop application creation same commits different forks of 1 repo in db. figure out can hash column in db unique , if have commit hash - skip it. dont know there big/small chance skip unique commit , not duplicate of existing commit.

both git , mercurial use sha1 generating hashes, probability of having same hash 2 different commits 1 git , 1 mercurial same of having same hash 2 different git commits.

svn not use hashes identify commits incremental revision numbers not have collision problem here


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