Database Management Systems

An organisation uses a computer to store and process information because it hopes for speed, accuracy, efficiency, economy etc. beyond what could be achieved using clerical methods; the objectives of using a DBMS must in ..... be the same although the justifications may be more indirect.

Early computer applications were based on existing clerical methods and stored information was ..... in much the same way as manual files.ed

But the computer's processing speed gave a potential for relating data from different sources to produce valuable management information, provided that some standardisation could be imposed over departmental boundaries: the idea emerged of the ..... database as a central resource.

Data is captured as close as possible to its point of origin and transmitted to the database, then ..... by anyone within the organisation who requires it.

However many ..... have become attached to this idea in practice, it still provides possibly the strongest motivation for the introduction of a DBMS in large organisations.

A DBMS gives some protection against change by taking care of basic storage and retrieval functions in a standard way, leaving the applications developer to concentrate on specific organisational requirements; changes in one of these areas need not have ..... elsewhere.

In general a DBMS is a substantial piece of software, the result of many man-years of effort, but because its development costs are spread over a number of purchasers it can probably provide more facilities than would be economic in ..... product.

The points discussed above are probably most relevant to the larger organisation using a DBMS for its administrative functions, the environment in which the idea of databases first originated; in other ..... the convenience of a DBMS may be the primary consideration.

The purchaser of a small business computer needs all the software to run it in package form, written so that the minimum of expertise is required to use it, and the same applies to departments (e.g. Research & Development) with special needs which cannot be ..... by a large centralised system.

When comparing database management systems it is obvious that some are designed in the expectation that professional DP staff will be available to run them, while others are aimed at the total ......