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Date: Fri, 10 Feb 2012 15:30:55 -0600
From: Jeremiah Jordan <jeremiah.jordan@morningstar.com>
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To: user@cassandra.apache.org
CC: Drew Kutcharian <drew@venarc.com>
Subject: Re: Deleting a column vs setting it's value to empty
References: <2DCBA779-C020-4B32-8940-499CAE7B73DB@venarc.com>
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Either one works fine.  Setting to "" may cause you less headaches as 
you won't have to deal with tombstones.  Deleting a non existent column 
is fine.

-Jeremiah

On 02/10/2012 02:15 PM, Drew Kutcharian wrote:
> 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
>