Data Network Language Design
Ms. Xiaoning Yan
"The effect of computer networks on our ability to access information
cannot be overstated. Today, anyone with access to the Internet can
quickly view or retrieve any files that any other Internet user has
chosen to make available".*
When we use this access to do a search, we find that often the
results of the search are not easily used to what we want because the
data stored on the Internet are unstructured and inconsistent.
This situation might be improved by setting up a new class of public
computer networks (Data Networks), where the computers query each other
to get answers that people need. A new language, called Data Network
Language (DNL), is developed in this thesis as a query language for a
Data Network. The data that are stored in a DNL database are structured
data, such as sets, relations or mathematical expressions.
In this thesis, the syntax and grammar rules of DNL are developed along
with a set of constructors that will be used for retrieval of data stored
in DNL database. A DNL lexical analyser and parser (generated by LEX and
YACC in UNIX) are also developed. Some illustrative examples are provided.
* David L. Parnas, McMaster Software Engineering Group, McMaster
Unviersity, Dept. of Computing and Software, Hamilton, ON, Canada.