How to define what DatabaseGenerated.Computed should compute?
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I am just doing my first steps with EF CodeFirst, especially with dataAnnotations.
Now I'm doing my best to understand the "DatabaseGenerated" attribute.
What I know so far:

- using this attribute gives me three options to handle creation of a property value: Computed, Id and None.
- using this attribute means, that the property can not be updated manually - it is done by the database 

So - as I can imagine what happens when using th "Id" option, I have no idea what happens when using "Computed" option. I red that this should tell the db to compute the field value. 

For example: field "*sum*" = field "*price*" + field "*shipping*".

But how can I use that in that way? I looked around and did not find any examples. Could you please help me?

Thx so far,

*CodeCannibal*