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On Fri, 2006-02-10 at 11:15 +0100, Lorenzo Gil Sanchez wrote:
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<FONT COLOR="#000000">How do I update the old objects and add the new attribute to them? I can </FONT>
<FONT COLOR="#000000">provide a default value for this attribute if that helps.</FONT>
<FONT COLOR="#000000">I know this is a common issue with application updates. I also know that </FONT>
<FONT COLOR="#000000">during the development phase the best thing I can do is remove the </FONT>
<FONT COLOR="#000000">Data.fs file and start again and that's what I'm currently doing. But </FONT>
<FONT COLOR="#000000">I'm worried about installing the application in the client machines and </FONT>
<FONT COLOR="#000000">two month later needing to add more fields to my content-types. If I </FONT>
<FONT COLOR="#000000">understand correctly one of the advantages of Zope3 is the support for </FONT>
<FONT COLOR="#000000">always-changing-applications. So how does it work in this particular </FONT>
<FONT COLOR="#000000">situation?</FONT>
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I think that Zope3 handles this problem through the concept of "generations".<BR>
Documentation and interfaces are available in package "zope.app.generations".<BR>
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Thierry<BR>
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