Processing Sequential Files

Previous chapters introduced the mechanics of creating and reading sequential files. This chapter introduces the two most important sequential-file processing problems: control breaks and the file update problem.

Both control breaks and the file update problem involve manipulating ordered sequential files so the chapter begins with a discussion of how sequential files are organized and the difference between ordered and unordered sequential files.

The next section discusses control-break problems. These normally occur when a hierarchically structured printed report has to be produced. But control breaks ...

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