Abstract

The dual scale topology optoelectronic processor (DSTOP) was developed for generalized matrix algebra.¹ Vector outer products are a particularly useful feature of the DSTOP architecture. Since the computation is performed electronically, a generalized function may be substituted for conventional numerical multiplication; this is especially useful in symbolic computations such as those required in relational databases. We have developed algorithms appropriate for DSTOP that use generalized outer products in the execution of relational algebraic operations.² The DSTOP processor serves as a decision subsystem in a relational database machine. The DSTOP relational algebraic processor is well suited to interface with 3D optical storage devices such as optical disks, photorefractive crystals or two-photon memories. The operations performed include joins, set difference, union, intersection and set division. Duplicate removal may also be performed in the support of the projection relational operator. The remaining relational operators, selection and Cartesian product, are not included. Cartesian products require no decision mechanism while selection, which is a unary operator, is best performed on a smaller, front end processor.

© 1991 Optical Society of America