Traditional File-Based Systems

 


Traditional File-Based Systems


File-Based Approach


A collection of application programs that perform services for the system end-users such as the production of reports. Each program defines and manages its own data.


File-based systems were an early attempt to computerize the manual filing system that we are all familiar with. For example, in an organization a manual file is set up to hold all external and internal correspondence relating to a project, product, task, client, or employee. 


Typically, there are many such files, and for safety they are labeled and stored in one or more cabinets. For security, the cabinets may have locks or may be located in secure areas of the building. In our own home, we probably have some sort of filing system which contains receipts, guarantees, invoices, bank statements, and such like. 


When we need to look something up, we go to the filing system and search through the system starting from the first entry until we find what we want. Alternatively, we may have an indexing system that helps locate what we want more quickly. For example, we may have divisions in the filing system or separate folders for different types of item that are in some way logically related. 


Although the file-based approach is largely obsolete, there are good reasons for studying it:


  • Understanding the problems inherent in file-based systems may prevent us from repeating these problems in database systems. In other words, we should learn from our earlier mistakes. Actually, using the word ‘mistakes’ is derogatory and does not give any cognizance to the work that served a useful purpose for many years. However, we have learned from this work that there are better ways to handle data.                                               
  • If you wish to convert a file-based system to a database system, understanding how the file system works will be extremely useful, if not essential.


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