Data Versioning

Does any body know if pgsql supports any kind of versioning of  binary 
objects or data. e.g. If I'm storing a binary file in a row of a table, I 
would want to see different versions of the same biary file. Everytime I do 
a write, the version number should be bumped up !!

Is it possible to do it in pgsql or any other databases.
I'm using JDBC for connecting to database.

thanks

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