Schema Evolution publication categorizer

Schema mappings are high-level specifications that describe the relationship
between two database schemas. Two operators on schema
mappings, namely the composition operator and the inverse operator,
are regarded as especially important. Progress on the study of
the inverse operator was not made until very recently, as even finding
the exact semantics of this operator turned out to be a fairly delicate
task. Furthermore, this notion is rather restrictive, since it is rare that
a schema mapping possesses an inverse.
In this paper, we introduce and study the notion of a quasi-inverse

A schema mapping is a high-level declarative specification of the relationship between two schemas; it specifies how data structured under one schema, called the source schema, is to be converted into data structured under a possibly different schema, called the target schema. Schema mappings are fundamental components for both data exchange and data integration. To date, a language for specifying (or programming) schema mappings exists. However, developmental support for programming schema mappings is still lacking.