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Name value pair (EAV) model


Name value pair (EAV) model

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SQLDev1
SQLDev1
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Great discussion here.
I'm having a similar dilemma. We are building a social component to our website and the requirements are that customers and or external application would be able to create a profile in our system with user define fields.

I've created a profile table with the basic info. firstname, lastname, photo etc...
Now I'm trying to figure out the best way to include the additional user defined fields and is where the EAV model came up. I've read in numerous blogs/sites to not do it unless absolutely necessary.

From these readings, I have not found that anyone has a good alternative. There is always some major deficiency in it.

Would it make sense to store the user defined fields in an xml column? or in my case would EAV work efficiently where i would only store a subset of the data in an EAV model?

The other option I have is making the middle layer do the column manipulation. So if I went with the EAV model, my select would only be ...
select ProfileID, Entity, value
from EAV_Profile
where Profileid = 1

an not the horrible select with numerous joins and case statements.

The rest of the formatting and logic would happen in the mid layer. Does this seem like

Any additional advise would be greatly appreciated.
Jeff Moden
Jeff Moden
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Group: General Forum Members
Points: 87374 Visits: 41113
Heh... c'mon.... EAV's and NVP's are cool. You can put the entire database in one table and you only have to worry about maintenance on one index. :-P:-P:-P

--Jeff Moden

RBAR is pronounced ree-bar and is a Modenism for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
Stop thinking about what you want to do to a row... think, instead, of what you want to do to a column.
If you think its expensive to hire a professional to do the job, wait until you hire an amateur. -- Red Adair

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