Lecture 2 — Wednesday , August 22 , 2007
نویسندگان
چکیده
Databases are typically stored in one of two formats. A horizontal representation, as shown above, is indexed by transaction ID and stores items in each transaction. A vertical representation, on the other hand, is indexed by item and stores transactions that each item occurs in. Different algorithms are tuned to work with different representations. In this lecture, we will focus on horizontal representations.
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تاریخ انتشار 2007