Primary keys are critical because they provide a way of distinguishing each record In a table. I. E. Searching a customer by ID number , see figure 6. 10) Foreign Key - is a primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables. Data Warehouse - is a logical collection of information, gathered from many different operational databases, that supports business analysis activities and decision- making tasks.
The primary purpose of a DO Is to combine Information, more specifically strategic information, throughout an organization into a single repository in such a way that the people who need that information can make decisions and ender-take business analysis. A key Idea is to collect information from multiple systems In a common location that uses a universal querying tool. Data Mart - contains a subset of data warehouse information. Data Warehouse vs.. Mart: warehouse - more organizational focus and mart- a more functional focus.
Data Mining - is the process of analyzing data to extract information not offered by raw data alone. Data milling can also begin at a summary Information level (coarse granularity) and progress through increasing levels of detail (drilling down), or the reverse (drilling up). Companies use these techniques to compile a complete picture f operations, all within a single view, allowing them to indemnify trends and Improvement forecasts. Business Intelligence - Information collected from multiple sources that analyzes patterns, trends, and relationships for strategic decision making.
Cluster Analysis - is a technique used to divide information sets into mutually exclusive groups such that the members of each group are as close together as possible to one another and the deferent groups are as far apart as possible. Clusters segments customer information to help organizations to Identify customers with similar behavioral traits, such as clusters of best customers, or OFF Local Area Network (LANA) -(leanest connects a group of computers in close proximity, such as in an office building, school ore home.
Lana allow sharing of files, printers, games and other resources. They also often connect to other Lana and wide area networks (WANTS) Wide Area Networks (WAN) - (Extranet) - spans a large geographic area such as a state, province or country (I. E. Internet). Essential for carrying out the day-to-day activities of many companies and government organizations, allowing them to transmit and receive information among their employees, customers, suppliers, business partners, and other organizations across ties, regions and countries around the world.
Metropolitan Area Network (MAN) - large computer network usually spanning a city. Mostly large companies, colleges, universities, that span a campus use an infrastructure supported by a MAN. Extranet - is an extension of an intranet that is available only to authorized Waves: Electric - Radio - Micro - Light - Network Protocols: Packet - a single unit of binary data routed through a network. Packers directly impact network performance Protocol - a standard that specifies the format of data as well as the rules to be followed during transmission.