Nursuhada Bt Abd Ghafar 4C BM111.
History of Data Warehousing.
I In the 1990’s executives became less
concerned with the day-to-day business operations and more concerned with
overall business functions
I The data warehouse provided the ability to
support decision making without disrupting the day-to-day operations, because:
§Operational information is mainly current – does not include
the history for better decision making
§Issue of quality information
§Without information history, it is difficult to tell how and
why things change over time.
Data Warehouse Fundamentals.
T Data
warehouse – a logical collection of information –
gathered from many different operational databases – that supports business
analysis activities and decision-making tasks
T The primary purpose of a data warehouse is to
combined information throughout an organization into
a single repository for decision-making purposes – data warehouse support only
analytical processing.
Data Warehouse Model.
B Extraction,
transformation, and loading (ETL) – a
process that extracts information from internal and external databases, transforms the information using a common set of
enterprise definitions, and loads the information into a data warehouse.
B Data warehouse then
send subsets of the information to data mart.
B Data mart – contains a subset of data warehouse
information
Multidimensional Analysis and Data Mining.
M Relational Database contain information in a
series of two-dimensional tables.
M In a data warehouse and data mart,
information is multidimensional, it contains layers of columns and rows
§Dimension –
a particular attribute
of information.
M Cube – common term for the
representation of multidimensional information
Q Once a cube of information is created, users
can begin to slice and dice the cube to drill down into the information.
Q Users can analyze information in a number of
different ways and with number of different dimensions.
Q Data
mining – the process of analyzing data to extract
information not offered by the raw data alone. Also known as "knowledge
discovery" – computer-assisted tools and techniques for sifting through
and analyzing vast data stores in order to find trends, patterns, and
correlations that can guide decision making and increase understanding.
Q To perform data mining users need data-mining
tools
§Data-mining tool – uses a variety of techniques
to find patterns and relationships in large volumes of information. E.g: retailers can use knowledge
of these patterns to improve the placement of items in the layout of a
mail-order catalog page or Web page.
Information Cleansing or Scrubbing.
I An organization must maintain high-quality
data in the data warehouse
I Information
cleansing or scrubbing – a process that weeds
out and fixes or discards inconsistent, incorrect, or incomplete information
I Occur during E.T.L process and second on the
information once if is in the data warehouse
I Contact information in an
operational system
Y Standardizing Customer
name from Operational Systems
Y Information cleansing
activities
S Accurate and complete
information
Business Intelligence.
S Business
intelligence – refers to applications and
technologies that are used to gather, provide access, analyze data, and
information to support decision making effort.
S These
systems will illustrate business intelligence in the areas of customer
profiling, customer support, market research, market segmentation, product
profitability, statistical analysis, and inventory and distribution analysis to
name a few
Y E.g: Excel,
Access
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