CS411 - Query Processing2 Final Scribe

because its not always possible to fit the relation

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Unformatted text preview: is check it in the dictionary. If the tuple does not exist, then it is outputted and added to the data structure. However, if it is, then it means that it is a duplicate. We are basically building a dictionary in the main memory. Furthermore, operators such as Grouping (union, etc) all follow this same use case. One- pass Algorithms Grouping: γcity, sum(price) (R) • Need to keep a dictionary in memory • Also store the sum(price) for each city...
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This note was uploaded on 01/28/2014 for the course CS 411 taught by Professor Staff during the Fall '08 term at University of Illinois, Urbana Champaign.

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