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Unformatted text preview: l (that is, a runtime strategy) for supporting
such applications. For this, an active database system uses rules that have up to
three components - an event, a condition, and an action. The event part of a rule
describes a happening to which the rule may be able to respond. The condition
part of the rule examines the context in which the event has taken place. The
action describes the task to be carried out by the rule if the relevant event has
taken place and the condition has evaluated to true. Such a rule is known as eventcondition-action or ECA-rule. In some cases, the event or the condition may be
ether missing or implicit. For instance, in the application discussed above, there is
no condition. Hence it is an example of event-action rule. The event is "quantity
below threshold value" and the action is "invoke the application for placing order".
Points to Remember
1. Data processing is defined as a series of actions or operations that converts
data into useful information. Thus, data is the raw material of information and just
as raw materials are transformed into finished products by a manufacturing
process, raw data is transformed into information by data processing.
2. A data processing system includes the resources such as people, procedures,
and devices that are used to accomplish the processing of data for producing
3. In data processing, storage of data is often conceptualized as a data storage
hierarchy, which normally consists of bit, character, field, record, file and
Multiple related bits are combined to form a character, multiple related
characters are combined to form a field, multiple related fields are combined to
form a record, multiple related records are combined to form a file, and multiple
related files are integrated to form a database.
5. The two standard methods used in data processing for organizing data are fileoriented approach and database-oriented approach.
In the file-oriented approach of organizing data, an application's data is
organized into one or more files and the application program processes the data
stored in these files to generate the desired output. A set...
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- Spring '14