2. A deductive database and logic programming system based on Horn-clause rules with extensions like SQL's group-by and aggregation operators. CORAL was developed at the University of Wisconsin-Madison. It is implemented in C++ and has a Prolog-like syntax.
Many evaluation techniques are supported, including bottom-up fixpoint evaluation and top-down backtracking. Modules are separately compiled; different evaluation methods can be used in different modules within a single program. Disk-resident data is supported via an interface to the Exodus storage manager. There is an on-line help facility. It requires AT&T C++ 2.0 (or G++ soon) and runs on Decstation and Sun-4.