Question: 1. Serge Abiteboul and Anthony Bonner. "Objects and Views." Proc. ACM International Conference on Management of Data, Denver, Colo. (May 1991). Proposes a view mechanism for 00 systems. The proposal appears to be the first to take behavior (methods) into account.
2. Malcolm P. Atkinson and 0. Peter Buneman. Types and Persistence in Database Pro-gramming Languages." ACM Comp. Sun). 19, No. 2 (June 1987). This paper is recommended as the best starting point for reading in the area of database programming languages in general.