A Spreadsheet Algebra for a Direct Data Manipulation Query Interface

13 years 11 months ago

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— A spreadsheet-like “direct manipulation” interface is more intuitive for many non-technical database users compared to traditional alternatives, such as visual query builders. The construction of such a direct manipulation interface may appear straightforward, but there are some signiﬁcant challenges. First, individual direct manipulation operations cannot be too complex, so expressive power has to be achieved through composing (long) sequences of small operations. Second, all intermediate results are visible to the user, so grouping and ordering are material after every small step. Third, users often ﬁnd the need to modify previously speciﬁed queries. Since manipulations are speciﬁed one step at a time, there is no actual query expression to modify. Suitable means must be provided to address this need. Fourth, the order in which manipulations are performed by the user should not affect the results obtained, to avoid user confusion. We address the aforementioned challen...

Bin Liu, H. V. Jagadish

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