PFL (Persistent Functional Language) was developed
during the 1990s by Alex Poulovassilis, Carol Small, Pete Newson, Swarup Reddi and David
Sutton at Birkbeck, and Simon Courtenage at the
University of Westminster. Initially, PFL aimed to combine the
respective advantages of the Functional Data Model (see right)
with the deductive capabilities of logic-based languages.
Subsequently, we extended PFL with Event-Condition-Action (ECA) rules.
This work was funded by a series of research grants
in database languages. See here for relevant publications. See also the book The Functional Approach to Data Management: modeling, analyzing and integrating heterogeneous data, Springer, 2004.