Schema Evolution publication categorizer

Mappings between different representations of data are the essential building blocks for
many information integration tasks. A schema mapping is a high-level specification
of the relationship between two schemas, and represents a useful abstraction that specifies
how the data from a source format can be transformed into a target format. The development
of schema mappings is laborious and time-consuming, even in the presence of tools that facilitate
this development. At the same time, schema evolution inevitably causes the invalidation of

A schema mapping is a specification that describes how data from a source schema is to be mapped to a target schema. Once the data has been transferred from the source to the target, a natural question is whether one can undo the process and recover the initial data, or at least part of it. In fact, it would be desirable to find a reverse schema mapping from target to source that specifies how to bring the exchanged data back.

The inversion of schema mappings has been identified as one of the fundamental operators for the development of a
general framework for metadata management. In fact, during the last years three alternative notions of inversion for

A schema mapping is a specification that describes how data
structured under one schema (the source schema) is to be
transformed into data structured under a different schema
(the target schema). Although the notion of an inverse of
a schema mapping is important, the exact definition of an
inverse mapping is somewhat elusive. This is because a
schema mapping may associate many target instances with
each source instance, and many source instances with each
target instance. Based on the notion that the composition
of a mapping and its inverse is the identity, we give a formal