Data restructuring is often an important part of information processing. This paper describes an automatic data restructurer which takes over, from the user, the “thinking and coding” process normally associated with writing algorithms for data restructuring.

One of the most difficult tasks in database design is the collection of relevant information needed for database design. This information can be separated into two categories: information about the processes which use, modify or produce the data, and information about the data which is used, modified, or produced by the processes. This paper describes a "forms" oriented requirements specification facility as a formal means for capturing the information crucial for database design. Both kinds of information are expressible by the proposed structured forms specification. Furthermore, not only the application usage, but also the integrity constraints that must be maintained in the database can be captured in a concise, unambiguous and machine manipulable manner. The concepts underlying the forms approach are few and simple, hence it is easy to use for the database designer and can be understood by non-computer specialists. This facilitates the cooperation from users to participate in the specification of database application requirements.

Business activities, in general, involve data processing (such as queries, extraction, manipulation, and restructuring of data, etc.) as well as conventional office work centered around preparation, distribution, and filing and retrieval of documents. Convinced that most of these activities can be expressed in terms of forms, we present in this paper a formal means for specification of forms processing. The underlying concept is that business functions can be decomposed into meaningfuliy connected form processes where each process either produces or modifies a form. Powerful constructs are provided so that most of the common data processing activities can be expressed in a very high level, concise, and yet compilable manner.

EXPRESS is an experimental prototype data translation system which can access a wide variety of data and restructure it for new uses. The system is driven by two very high level nonprocedural languages: DEFINE for data description and CONVERT for data restructuring. Program generation and cooperating process techniques are used to achieve efficient operation. This paper describes the design and implementation of EXPRESS. DEFINE and CONVERT are summarized and the implementation architecture presented. The DEFINE description is compiled into a customized PL/1 program for accessing source data. The restructuring specified in CONVERT is compiled into a set of customized PL/1 procedures to derive multiple target files from multiple input files. Job steps and job control statements are generated automatically. During execution, the generated procedures run under control of a process supervisor, which coordinates buffer management and handles file allocation, deallocation, and all input/output requests. The architecture of EXPRESS allows efficiency in execution by avoiding unnecessary secondary storage references while at the same time allowing the individual procedures to be independent of each other. Its modular structure permits the system to be extended or transferred to another environment easily.

This paper describes in detail a translation definition language, CONVERT, for specifying the mapping of the instances of source items, which may be components of one or more files, into instances of target data, which may constitute multiple files.The language is designed for the class of users who are familiar with the logical aspects of their data, know what they want to be done, but do not want to be concerned with the details of how to accomplish it. It is high level and non-procedural according to current standards.The language provides very powerful and highly flexible restructuring capability. Although primarily designed for hierarchically structured data, it is applicable to other kinds of data structures as well. It is believed that the language can handle all common processes required in a data translation. Furthermore, the simple underlying concepts enable the users to visualize the translation processes, thus making data conversion a much simpler task. Examples to illustrate the languages' applications are included.