Raghav Kaushik

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Data cleaning based on similarities involves identification of "close" tuples, where closeness is evaluated using a variety of similarity functions chosen to suit the domain and application. Current approaches for efficiently implementing such similarity joins are tightly tied to the chosen similarity function. In this paper, we propose a new primitive(More)
In this paper, we ask if the traditional relational query acceleration techniques of summary tables and covering indexes have analogs for branching path expression queries over tree- or graph-structured XML data. Our answer is yes --- the forward-and-backward index already proposed in the literature can be viewed as a structure analogous to a summary table(More)
XML and other semi-structured data may have partially specified or missing schema information, motivating the use of a structural summary which can be automatically computed from the data. These summaries also serve as indices for evaluating the complex path expressions common to XML and semi-structured query languages. However, to answer all path queries(More)
We consider the problem of learning a record matching package (classifier) in an active learning setting. In active learning, the learning algorithm picks the set of examples to be labeled, unlike more traditional passive learning setting where a user selects the labeled examples. Active learning is important for record matching since manually identifying a(More)
Incorporating the skyline operator inside the relational engine requires solving the cardinality estimation and the cost estimation problem, hitherto unaddressed. We propose robust techniques to estimate the cardinality and the computational cost of Skyline, and through an empirical comparison, show that our technique is substantially more effective than(More)
Autocompletion is a useful feature when a user is doing a look up from a table of records. With every letter being typed, autocompletion displays strings that are present in the table containing as their prefix the search string typed so far. Just as there is a need for making the lookup operation tolerant to typing errors, we argue that autocompletion also(More)
This paper describes the design of the Cipherbase system. Cipherbase is a full-fledged SQL database system that achieves high performance and high data confidentiality by storing and processing strongly encrypted data. The Cipherbase system incorporates customized trusted hardware, extending Microsoft’s SQL Server for efficient execution of queries using(More)
Several methods have been proposed to evaluate queries over a native XML DBMS, where the queries specify both path and keyword constraints. These broadly consist of graph traversal approaches, optimized with auxiliary structures known as structure indexes; and approaches based on information-retrieval style inverted lists. We propose a strategy that(More)
Record matching is the task of identifying records that match the same real world entity. This is a problem of great significance for a variety of business intelligence applications. Implementations of record matching rely on exact as well as approximate string matching (e.g., edit distances) and use of external reference data sources. Record matching can(More)