Schema Evolution publication categorizer

We provide a principled extension of SQL, called
SchemaSQL , that offers the capability of uniform
manipulation of data and meta-data in relational
multi-database systems. We develop a
precise syntax and semantics of SchemaSQL in
a manner that extends traditional SQL syntax
and semantics, and demonstrate the following. (1)
SchemaSQL retains the flavour of SQL while supporting
querying of both data and meta-data. (2)
It can be used to represent data in a database
in a structure substantially different from original
database, in which data and meta-data may