infs Ch 7

Dependent data mart

-does not have own source systems -data comes from data warehouse

Integrated

-integrates analytically useful data from various operational databases

Steps in develping DWH

-requirements -modeling -creation of warehouse -front end -ETL -Deployment -Use

Data Warehouse

created within an organization as a separate data store whose primary purpose is data analysis -created for efficiency and to not diminish performance or operational tasks

logical modeling

creating of the data warehouse data model that is implementable by the software

front end

designing and creating applications for indirect use by the end users

Detailed and/or summarized data

may include one or both depending on purpose data at the finest level is the most powerful

creating ETL infrastructure

most time and resource consuming part

Retrieval of analytical information

not meant for direct data entry by the users data in the warehouse can be retrieved only, not subject to change, read only

ETL infrastructure

-retrieval of data from operational databases into the data warehouses -Extracting analytically useful data -transforming data so that it conforms to the structure of the target data warehouse -loading the transformed and quality assured data into the target data warehouse

data warehouse components

-source systems -ETL infrastructure (extraction-transformation-load) -data warehouse -front end applications

Requirement collection, definition, and visualization

-specifying the desired capabilities and functionalities of the future data warehouse -requirements can be found through interviewing various stakeholders -should be in a written document -then conceptual model

Independent data mart

-stand alone data mart, created in the same fashion as the data warehouse -has own source systems and ETL infrastructure

structured repository

-the data warehouse is a database containing analytically useful information -structure represented in metadata -any database

Data mart

a data store based on the same principles as a data warehouse, but with a more limited scope narrower than organization wide

source systems

operational databases or other operational data repositories, can include external data sources

administration and maintenance

performing activities that support the data warehouse end user, including dealing with technical issues

front-end applications

provide access to the data warehouse for users who are engaging in indirect use

Subject-oriented

refers to the fundamental difference in the purpose of an operational database system and a data warehouse -operational supports a specific business operation -warehouse analyzes specific business subject areas

deployment

releasing the data warehouse and front-end for use by end users

data warehouse

target system

Time Variant

the data warehouse contains slices or snapshots of data from different periods of time across its time horizon

Formal definition of data warehouse

the data warehouse is a structured repository of integrated subject-oriented, enterprise-wide, historical, and time-variant data. The purpose of a data warehouse is the retrieval of analytical information. A data warehouse can store detailed and summarized data

Enterprise-wide

the data warehouse provides an organization-wide view of the analytically useful information It contains

Analytical information

the information collected and used in support of analytical tasks

operational information

the information collected and used in support of day to day operational needs

Historical

the larger time horizon in the data warehouse than in operational databases

data warehouse use

the retrieval of the data in the data warehouse indirect and direct use

creating the data warehouse

use dbms to implement the model as an actual data warehouse