Entity Attribute Value (EAV) Vs. XML Column For New Product Attributes?
Mar 21, 2011
I have an existing, mature schema to which we need to add some new Product attributes. For example, we have Products.Flavor, and now need to add new attributes such as Weight, Fragrance, etc. Rather than continue to widen the Products table, I am considering a couple of other options. First is a new Attributes table, which will effectively be a property bag for arbitary attributes, and a ProductsAttributes table to store the mappings (and values) for a particular product's attributes. This is the Entity-Attribute-Value (EAV) pattern, as I've come to understand it. The other option is to add a new column to the Products table called Attributes, which is of type XML. Here, we can arbitrarily add attributes to any product instance without adding new tables.
What are the pros/cons to each approach? I'm using SQL Server 2008 and ASP.NET 4.0.
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