Message-ID: <3B68BF19.3020306@xythos.com>
Date: Wed, 01 Aug 2001 19:46:49 -0700
From: Barry Lind <barry@xythos.com>
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To: Sunit Bhatia <bhatia_sunit@hotmail.com>
CC: pgsql-general@postgresql.org, pgsql-jdbc@postgresql.org
Subject: Re: Data Versioning
References: <F122yh133tYwlib4g3S00012664@hotmail.com>
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You should be able to easily design a database schema that does what you 
want.  For example two tables,

files
------
file_id (PK)
file_name text
...

file_versions
-------------
file_version_id (PK)
file_id (FK to files.file_id)
version integer not null
data oid not null
...

Then when your application creates a new file you would insert a row 
into both the files and file_versions table.  When your application 
'updates' a file it just inserts into the file_versions table the new 
version.

There is no explicit support for what you are trying to do native, and I 
don't know of any other databases that support that type of 
functionality either (at least I know Oracle does not).

thanks,
--Barry


Sunit Bhatia wrote:

> 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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