Introduction
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Intro¶
- Basically, there are two modes in which databases are used
Online Transaction Processing: a large number of users use the database, with each user retrieving relatively small amounts of data, and performing small updates.
data analytics: processing of data to draw conclusions, and infer rules or decision procedures, which are then used to drive business decisions. - The field of data mining combines knowledge-discovery techniques invented by artificial intelligence researchers and statistical analysts with efficient implemen tation
- The field of data mining combines knowledge-discovery techniques invented by artificial intelligence researchers and statistical analysts with efficient implemenatation techniques that enable them to be used on extremely large databases.
File-Processing Systems(supported by a conventianal operating system)¶
- Majarity Disadvantages:
Data redundancy and inconsistency
Difficulty in accessing data: t conventional file-processing environments do not allow needed data to be retrieved in a convenient and efficient manner. More responsive data-retrieval systems are required for general use.
Data isolation: because data are scattered in various files, and files may be in different formats, writing new application programs to retrieve the appropriate data is difficult.
Integrity problems: The data values stored in the database must satisfy certain types of consistency constraints. However, when new constraints are added, it is difficult to change the programs to enforce them. The problem is compounded when constraints involve several data items from different files