Control break
In computer programming a control break is a change in the value of one of the keys on which a file is sorted which requires some extra processing.[1][2][3][4] For example, with an input file sorted by post code, the number of items found in each postal district might need to be printed on a report, and a heading shown for the next district. Quite often there is a hierarchy of nested control breaks in a program, e.g. streets within districts within areas, with the need for a grand total at the end. Structured programming techniques have been developed to ensure correct processing of control breaks in languages such as COBOL and to ensure that conditions such as empty input files and sequence errors are handled properly.[5][6]
With fourth generation languages such as SQL, the programming language should handle most of the details of control breaks automatically.[7][8][9]
References[edit]
- ^ Computer Programming Languages in Practice: Made Simple Computerbooks, 2014, page 32-227
- ^ Logic and Structured Design for Computer Programmers, 2001, page 74-390
- ^ Programming Logic and Design, Introductory, 2014
- ^ Introduction to computer programming RPG, 1972, pages 1-8
- ^ Academic Press Dictionary of Science and Technology, 1992, pages 307-2112
- ^ Introduction to computer programming structured COBOL, 1977, pages 8-20
- ^ Joe Celko's SQL for Smarties: Advanced SQL Programming, 2010, page 528
- ^ Oracle SQL, 2003, pages 76-201
- ^ Relational Databases: State of the Art Report 14:5 2014, page 46