  This thesis presents practical suggestions towards the implementation of the
hyperset approach to semi-structured databases and the associated query
language Delta. This work can be characterised as part of a top-down approach
to semi-structured databases, from theory to practice. The main original part
of this work consisted in implementation of the hyperset Delta query language
to semi-structured databases, including worked example queries. In fact, the
goal was to demonstrate the practical details of this approach and language.
The required development of an extended, practical version of the language
based on the existing theoretical version, and the corresponding operational
semantics. Here we present detailed description of the most essential steps of
the implementation. Another crucial problem for this approach was to
demonstrate how to deal in reality with the concept of the equality relation
between (hyper)sets, which is computationally realised by the bisimulation
relation. In fact, this expensive procedure, especially in the case of
distributed semi-structured data, required some additional theoretical
considerations and practical suggestions for efficient implementation. To this
end the 'local/global' strategy for computing the bisimulation relation over
distributed semi-structured data was developed and its efficiency was
experimentally confirmed.
