Even the earliest business computer systems were used to process business records and produce information. They were generally faster and more accurate than equivalent manual systems. These systems stored groups of records in separate files, and so they were called file processing systems. Although file processing systems are a great improvement over manual systems, they do have the following limitations:

 Data is separated and isolated.

 Data is often duplicated.

 Application programs are dependent on file formats.

 It is difficult to represent complex objects using file processing systems. Data is separate and isolated. Recall that as the marketing manager you needed to relate sales data to customer data. Somehow you need to extract data from both the CUSTOMER and ORDER files and combine it into a single file for processing. To do this, computer programmers determine which parts of each of the files are needed. Then they determine how t ... Read more »