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From: Drew Kutcharian <drew@venarc.com>
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Subject: Deleting a column vs setting it's value to empty
Date: Fri, 10 Feb 2012 12:15:46 -0800
Message-Id: <2DCBA779-C020-4B32-8940-499CAE7B73DB@venarc.com>
To: user@cassandra.apache.org
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Hi Everyone,

Let's say I have the following object which I would like to save in =
Cassandra:

class User {
  UUID id; //row key
  String name; //columnKey: "name", columnValue: the name of the user
  String description; //columnKey: "description", columnValue: the =
description of the user
}

Description can be nullable. What's the best approach when a user =
updates her description and sets it to null? Should I delete the =
description column or set it to an empty string?

In addition, if I go with the delete column strategy, since I don't know =
what was the previous value of description (the column could not even =
exist), what would happen when I delete a non existent column?

Thanks,

Drew