A-level Computing/Advanced Systems Development/Databases
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Database Concepts
Traditional File Approach
Most organisations began information processing on a small scale, buying a computer for perhaps one or two individual applications, and then computerising other departments one by one. Applications were developed independently, and files of information relevant to one particular department were created and processed by dozens or even hundreds of separate programs. This led to several problems such as:
Data redundancy - The same data was duplicated in many different files.
Data inconsistency - When the same items of data were held in several different file, the data has to be updated in each separate file when it changes.