Details of Grant 

EPSRC Reference:	GR/J49044/01
Title:	EXTENDING FUNCTIONAL DATABASE LANGUAGES TO UPDATE COMPLETENESS
Principal Investigator:	Small, Dr C
Other Investigators:
Researcher Co-Investigators:
Project Partners:
Department:	Computer Science and Information Systems
Organisation:	Birkbeck College
Scheme:	Standard Research (Pre-FEC)
Starts:	01 October 1993	Ends:	30 September 1995	Value (£):	75,841
EPSRC Research Topic Classifications:	Information & Knowledge Mgmt
EPSRC Industrial Sector Classifications:
Related Grants:
Panel History:
Summary on Grant Application Form
(a) To extend an existing functional database language - PFL - to allow programs to update all aspects of the database.(b) To evaluate the expressiveness, efficiency and ease of use of these extensions with respect to a road traffic accident application.(c) To optimise the update facilities in the light of the experience gained in (b)Progress: We have replaced PFL's existing Hindley-Milner type system with a type system based upon Wadler's steadfast type system, and introduced built-in functions which allow database relations to be updated destructively. The type system ensures that such destructive updates are safe , in the sense that expression evaluation is still confluent.We are evaluating the modified PFL system with respect to road traffic accident database containing 70 relations, each containing and 12,000 tuples. The performance of the modified system is satisfactory for databases of this size, although we have identified several problems with the ease of use of the type system. The first is that the types inferred by the new type system are much more difficult for a naive user to understand that the types inferred by the old type system. The second is that several useful syntactic constructions - such as list abstractions - cannot be used when writing update programs. During the remainder of the project we shall address these problems, and show the correctness of our type system.References: Wadler, P. Is There A Use For Linear Logic?ACM/IFIP Symposium on Partial Evaluation and Semantics Based Program Manipulation, 1991.Sutton, D. and Small, C. Extending Functional Database Languages to Update Completeness.13th British National Conference on Databases, 1995 (to appear).
Key Findings
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Potential use in non-academic contexts
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Impacts
Description This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk Summary Date Materialised
Sectors submitted by the Researcher
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Project URL:
Further Information:
Organisation Website:	http://www.bbk.ac.uk/