PSQL: An Efficient Pictorial Database System.

Pictorial databases require efficient and direct spatial search based on the analog form of spatial objects and relationships instead of search based on some cumbersome alphanumeric encodings of the pictures. This paper briefly describes PSQL, a query language which allows pictorial domains to be presented to the user in their analog form and allows him to do direct manipulation on the objects found on those domains. Direct spatial search and computation on the pictures is done using efficient data structures, R- and R+-trees (multi-dimensional B- trees), which are excellent devices for searching spatial objects and relationships found on pictures