Entity with more 200 attributes

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Entity with more 200 attributes

Hamid
I have been introduced to Anchor Modeling 2 months ago when I started my new project that attributes of my entity are changing. I also need to keep historical data for my entity with in mind this is my warehouse. This entity will go to have 200 to 300 attributes. I plan to use Anchor modeling because it fits very well to my requirement.

Only thing that is in mind for last 2 months is performance with all those attribute.

I would appreciate if someone can help me with that if you think there would be problem with performance.
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Re: Entity with more 200 attributes

Olle
We have done tests (http://www.anchormodeling.com/wp-content/uploads/2010/09/Performance-Testing.zip) that show better performance in an AM model with a large number of attributes than in a 3NF model, when you don’t fetch all attributes at the same time (select * from …).

If you do select * you will not use the benefit of table elimination and your performance will most likely be worse than a 3NF model, but it could still be better if there are many versions of your data and attributes are historized asynchronously with respect to each other, or if you have where-conditions that are very selective and over columns for which the database has collected statistics, or when data is sparse.

AM models are very good when you have sparse data because you will only store data that has been specified. Null values correspond to the absence of rows in Anchor Modeling, resulting in less data to scan during query execution.

If your data is dense, static, and you often need to fetch all attributes at the same time in queries that have few or no conditions (and therefore result in big joins), then performance will suffer.
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Re: Entity with more 200 attributes

Hamid
Thanks for quick response.

One more question (I know this could be too much): Do you have any tools that we can add to the model in bulk?

Thanks
Hamid
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Re: Entity with more 200 attributes

Olle
Hi,
I don’t think I understand your question. Could you please elaborate the question?
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Re: Entity with more 200 attributes

Hamid
Hi,

we have about 200 to 300 attributes that we want to add to our DB model. If we are going to add them through Anchor modeling tool it takes too long. We built a simple application to add these attribute to XML model. it works but generated SQL server svript is not workong properly.

So I was wondering if you have such a tools we can use to add these attributes in one batch.


Also do you have stand alone modeling tool?

Thanks
Hamid
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Re: Entity with more 200 attributes

Olle
Hi,
Sorry but we have no tool for bulk-adding attributes to a model.
I do think adding attributes in the xml schema is the right way to go...

You can download the source code from http://www.anchormodeling.com/?page_id=494 and install it locally on a webserver to have a standalone version of the modeling tool.

/Olle

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Re: Entity with more 200 attributes

Hamid
Thanks. this is wonderful.

Hamid