Compare documents with hash and checksum

Hi to everyone,

we are having a doubt about if the content server (the old Livelink) in 10.5 version keeps in somewhere the hash code of the documents.

The fact is that before we add a document in the content server, we have to know if that document is already in the content server compairing its content. If that document with the same content is in the content server, we will not add the document. So we think about using an axiliar table to keep the codes of the documents that are already added, but perhaps Livelink keeps this information in some way.

Thanks in advance.

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Pramod_Mohandas

Hi Diana,

To the best of my knowledge, CS does not maintain any such table from which contains checksum values of every document stored on it.

What you could try, and this is only a suggestion, is to track down the document, if one already exists in CS, download it to the TEMP directory and then hash check the file before the new document is uploaded into CS. I don't remember CS having any OOTB functionality to hash check a given file as well.

You would need to achieve that functionality from outside the purview of CS I guess.

Thanks,

Pramod Mohandas

Ferdinand Prantl

If you want to save space in the storage only, you can combine the Livelink with the Archive Server. The Archive has a feature single-instance-archiving, which stores the same content (document) only once, regardless how many people upload it how many times. It is transparent on the outside of the Archive. It is useful for e-mail archiving, for example, if all people get the same attachment and all mailboxes are archived.

Because it is a feature of the Archive you cannot detect it in Livelink. If you want to prevent the user to from uploading the same content twice to Livelink, you'd have to implement a hook using a table with checksums, as you said, for example. If nobody wrote such module yet.

Diana García Rodríguez

Pramod, Ferdinand,

thanks for your answers. Now I am sure that there is no place in the content server where the hash or checksum of the documents are kept, so the first approach to solve this issue will be to store the hash of the documents outside the content server in an axuliar table, for example.

It is a good idea using Archive Server if it has an option to keep only once the documents with the same content. I thought that this option was only for email archiving, but I is a good new to know that is available for documents too.

Thanks!