The 1981 ACM Turing Award Lecture, Delivered at ACM ‘81, Los
Angeles, ,California, November 9, 1981
the growth in demands from end users is outstripping the capability of
data processing departments to implement the corresponding application
programs …
DBMS highly successful as instruments of data control
introduction of database management systems would markedly increase
the productivity of application programmers by removing many of their
problems in handling input and output files …
prior relational model
burden application programmers with numerous concepts that were
irrelevant to their data retrieval and manipulation tasks
no commands for set processing — iterative loops
need of end users for direct interaction with database, particularly
interaction of an unanticipated nature — a query capability
no sharp distinction between the programmer’s (logical) view of data
and the (physical) representation of data in storage.
… storage-oriented concepts were an integral part of … the adverse
impact on development productivity of requiring programmers to
navigate along access paths to reach the target data …
avoid the need for subsequent changes in the data description that, in
turn, would force coding changes in application programs
2 motivation
data independence objective
a sharp and clear boundary between the logical and physical aspects
of database management (including database design, data retrieval, and
data manipulation)
communicability objective
make the model structurally simple, so all programs … have a
common understanding of the data, and could therefore communicate with
one another about the database …
3 the relational model
discard all those data structuring concepts … and take a fresh look
at the addressing of data …