Storage and querying of E-commerce data

New generation of e-commerce applications require data schemas that are constantly evolving and sparsely populated. The conventional horizontal row representation fails to meet these requirements. We represent objects in a vertical format storing an object as a set of tuples. Each tuple consists of an object identifier and attribute name-value pair. Schema evolution is now easy. However, writing queries against this format becomes cumbersome. We create a logical horizontal view of the vertical representation and transform queries on this view to the vertical table. We present alternative implementations and performance results that show the effectiveness of the vertical representation for sparse data. We also identify additional facilities needed in database systems to support these applications well.