A control break is a change in category within a database to allow a computer to calculate subtotals. Control breaks can be necessary for certain kinds of operations that require logic to break up the information into meaningful chunks. A human being could quickly find the natural breaks in a table of information and process them, but a computer needs cues. Programmers can insert breaks at a variety of intervals, and users can create their own as long as they fit within the program’s parameters.
In a simple example, a college might maintain a database of current students. Staff might want to be be able to sort this data in a number of different ways. They could request breakdowns of students by state, province, or country, for example. They might want to look at the number of students in a given year, people in particular majors, and so forth. Control breaks can create separate categories within the database to allow the computer to do this.
Nested category creation is possible. In the student database, for example, one control break could be by county or similar unit of local government, with another by state or province, and a final control break by country. Personnel could request subtotals at each different control break; for example, they might want to know that of the 150 students from the United States, 70 are from Mississippi. Having breaks at the nation and state level allows the computer to return this data.
This can be useful in a wide variety of databases, from bookkeeping programs to title and deed records. Control breaks allow for detailed database management within a single database, without the need to create new files and entries for sorting different kinds of information. This makes analytical processes possible. Accountants preparing annual reports, for example, can total profits and losses by quarter, business sector, and other parameters.
Database programs may have control breaks built in automatically by designers, and users can add more, if they follow the program’s specific syntax. It is important to make sure the control break covers the desired fields, as accidental inclusions could create errors. People may also want to think about how others might use and organize the data when they set up control breaks. Advance planning can reduce the risk of problems that might make it harder to access the database and extract needed information in the future.
