Building a user interface using SQL Forms and an intermediate table.

摘要

There is usually a trade-off between flexibility and ease of use when a user interface is designed. This paper discusses a data retrieval interface that does not require end users to be ORACLE SQL*Plus programmers or to understand the structure of the database and offers them a very powerful and flexible access to the database. This interface is the front-end to a decision support system being designed and prototyped at Oak Ridge National Laboratory (ORNL). The interface develops the ''where'' clause of a SQL select statement for the user based on selections the user makes and stores and then uses those choices to query a target table. Through SQL*Forms screens, reference data tables are used as a source of values from which users choose data or by which user entries are validated. The user's choices are stored in an intermediate table. Then the system builds a query for the target table(s) using an operating system script in which the value and column names in the intermediate table are used to form the ''where'' clause. The query is executed and data are retrieved. 5 figs.