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A symbolic image is an array representing a set of objects and a set of direction relations among them. Symbolic images can be the source for retrieving direction relations via the Pictorial Query-by-Example (PQBE) language, a visual language which generalises from the example given by the user and is based on skeleton images which are by themselves symbolic images.

This paper presents an implementation of the PQBE language. The PQBE language is enriched with SQL-like predicates for non-spatial attributes and symbolic images are combined with a relational database scheme in a prototype visual database system, which integrates spatial and non-spatial management.