Data Warehousing Fundamentals A Comprehensive Guide for IT Professionals phần 6 potx

... Data 123 AAAAA 234 BBBBB 345 CCCCC DATA STAGING Key Data 123 AAAAA 234 BBBBB 345 CCCCC DATA STAGING Key Data 123 AAAAA 234 BBBBB 345 CCCCC DATA STAGING Key Data 123 AAAAA 234 BBBBB 345 CCCCC DATA STAGING B EF O R AF TE R Key ... extracted data is raw data and it cannot be applied to the data warehouse. First, all the extracted data must be made usable in the data w...

Ngày tải lên: 08/08/2014, 18:22

... Chapter 2: ț Source data Production data Internal data Archived data External data ț Data staging Data extraction Data transformation Data loading ț Data storage ț Information delivery ț Metadata ț ... internal and external data sources form the source data architectural component. Source data governs the extraction of data for preparation and storage in the dat...

Ngày tải lên: 08/08/2014, 18:22

... organizations gather enterprise data from the source operational systems, move the data through a transformation and cleansing process, and store the data in data warehouses in a form suitable for ... data security a major concern for a Web-enabled data warehouse? 8. List any four features of the data Webhouse. 9. Name any two approaches for an OLAP system to funct...

Ngày tải lên: 08/08/2014, 18:22

... individual transactions to change the data there. Data updates are commonplace in an operational database; not so in a data warehouse. The data in a data warehouse is not as volatile as the data in an ... there is a data staging area. In this stag- ing area, the operational data is cleansed and transformed into a form suitable for place- ment in the data warehouse...

Ngày tải lên: 08/08/2014, 18:22

... 3-8 Integration of KM and data warehouse. Types of Metadata Metadata in a data warehouse fall into three major categories: ț Operational Metadata ț Extraction and Transformation Metadata ț End-User ... metadata contain all of this information about the operational data sources. Extraction and Transformation Metadata. Extraction and transformation metada- ta contain data about the...

Ngày tải lên: 08/08/2014, 18:22

... source operational systems, data extraction tools, data transformation tools, the data dictionary definitions, and other sources all contribute to the data warehouse metadata. Metadata management, ... above list of criteria as a guide while evaluating repository tools for your data warehouse. Metadata Integration and Standards For a free interchange of metadata within the...

Ngày tải lên: 08/08/2014, 18:22

... poten- tial effect of bad data. The low-priority data may be cleansed if you have any time and re- DATA QUALITY INITIATIVE 309 DATA QUALITY INITIATIVES DATA CONSUMER (User Dept.) DATA EXPERT (User ... Validate for allowable values The DBMS for Quality Control The database management system itself is used as a tool for data qualtiy control in many ways. Relational databas...

Ngày tải lên: 08/08/2014, 18:22

... just a couple of ex- amples. Review all the initialization parameters and set each appropriately. Data Arrays What are data arrays? Suppose in a financial data mart you need to keep monthly balances of ... suitable for low-selectivity data? Why? 9. What is data partitioning? Give two reasons why data partitioning is helpful in a data warehousing environment. 10. What is...

Ngày tải lên: 08/08/2014, 18:22

... start with a large volume of data, even a small percentage increase can result in substantial additional data. In the first place, a data warehouse may contain too much historical data. Data ... huge amounts of data that has taken years to gather and accu- mulate. The historical data may go back 10 or even up to 20 years. Before the data arrives at the data warehouse, y...

Ngày tải lên: 08/08/2014, 18:22

... summary list of processes in which metadata is significant for IT: ț Data extraction from sources ț Data transformation ț Data scrubbing ț Data aggregation and summarization ț Data staging ț Data ... with the data extraction and ending with information delivery, metadata is crucial for IT. As the development process moves through data extraction, data transformation,...

Ngày tải lên: 08/08/2014, 18:22