Schema Evolution publication categorizer

... it is rare that a schema mapping possesses an inverse. In this paper, we introduce and study the notion of a quasi-inverse of a ... negative results about the existence of quasi-inverses. In particular, we show that every LAV (local-as-view) schema mapping has a ...

Publication - huliganka - 04/17/2013 - 02:49 - 0 comments - 1 attachment

... or XML schemas, and can be independently designed. In addition to the source-to-target mappings, we consider as part of the ... at the target. We define the semantics of query answering in such an integration scenario, and design two novel algorithms, basic query ...

Publication - huliganka - 04/17/2013 - 00:38 - 0 comments - 1 attachment

... 666.47 KB Many problems in information integration rely on specifications, called schema mappings, that ... for both relational and nested data are well-known. In this work, we present a new formalism for schema mapping that extends these existing formalisms in two significant ways. First, our nested mappings allow for nesting and ...

Publication - huliganka - 04/17/2013 - 00:05 - 0 comments - 1 attachment

... be a Σ1-query. An (equivalent) reformulation of q1 in the presence of C is a Σ2-query, q2, such that q2 gives the same ... ∪ Σ2-database instance that satisfies C. In general, there may exist multiple such reformulations and choosing among ...

Publication - huliganka - 04/16/2013 - 23:38 - 0 comments - 1 attachment

... to translate data from one representation to another. In dynamic environments like the Web, data sources may change not only ... query capabilities. Such changes must be reflected in the mappings. Mappings left inconsistent by a schema change have to be ...

Publication - cat - 04/16/2013 - 10:49 - 0 comments - 1 attachment

... of heterogeneous data transformation and integration. In Clio, we have collected together a powerful set of data management techniques that have proven invaluable in tackling these difficult problems. In this paper, we present the underlying ...

Publication - massmann - 04/16/2013 - 10:38 - 0 comments - 1 attachment

... Schemas evolve over time to accommodate the changes in the information they represent. Such evolution causes invalidation of ... depending on the schemas, such as schema mappings. In a heterogenous environment, where cooperation among data sources depends ...

Publication - cat - 04/16/2013 - 09:16 - 0 comments - 1 attachment