Data Warehousing Assignment
Q. 1. With necessary diagram explain about data warehouse development life cycle .
Ans : Introduction to data warehouses. Data warehouse development lifecycle (Kimball’s approach)
Q. 2. What is Metadata ? What is it’s uses in Data warehousing Archietechture ?
Ans : In simple terms, meta data is information about data and is critical for not only the business user but also data warehouse administrators and developers. Without meta data, business users will be like tourists left in a new city without any information about the city, and data warehouse administrators will be like the town administrators who have no idea about the size of the city or how fast it is growing.
Despite its criticality, meta data continues to remain the most neglected part of many data warehousing projects. "We shall worry about it later" is usually the approach.
Different data warehousing systems have different structures. Some may have an ODS (operational data store), while some may have multiple data marts. Some may have a small number of data sources, while some may have dozens of data sources. In view of this, it is far more reasonable to present the different layers of a data warehouse architecture rather than discussing the specifics of any one system.
In general, all data warehouse systems have the following layers:
Data Source Layer
Data Extraction Layer
Staging Area
ETL Layer
Data Storage Layer
Data Logic Layer
Data Presentation Layer
Metadata Layer
System Operations Layer
The picture below shows the relationships among the different components of the data warehouse architecture:
Metadata Layer
This is where information about the data stored in the data warehouse system is stored. A logical data model would be an example of something that's in the metadata layer. A metadata tool is often to used to manage metadata.
Q. 3. Write briefly about four ETL tools. What is Transformations? Briefly explain the basic
Ans : Introduction to data warehouses. Data warehouse development lifecycle (Kimball’s approach)
Q. 2. What is Metadata ? What is it’s uses in Data warehousing Archietechture ?
Ans : In simple terms, meta data is information about data and is critical for not only the business user but also data warehouse administrators and developers. Without meta data, business users will be like tourists left in a new city without any information about the city, and data warehouse administrators will be like the town administrators who have no idea about the size of the city or how fast it is growing.
Despite its criticality, meta data continues to remain the most neglected part of many data warehousing projects. "We shall worry about it later" is usually the approach.
Different data warehousing systems have different structures. Some may have an ODS (operational data store), while some may have multiple data marts. Some may have a small number of data sources, while some may have dozens of data sources. In view of this, it is far more reasonable to present the different layers of a data warehouse architecture rather than discussing the specifics of any one system.
In general, all data warehouse systems have the following layers:
Data Source Layer
Data Extraction Layer
Staging Area
ETL Layer
Data Storage Layer
Data Logic Layer
Data Presentation Layer
Metadata Layer
System Operations Layer
The picture below shows the relationships among the different components of the data warehouse architecture:
Metadata Layer
This is where information about the data stored in the data warehouse system is stored. A logical data model would be an example of something that's in the metadata layer. A metadata tool is often to used to manage metadata.
Q. 3. Write briefly about four ETL tools. What is Transformations? Briefly explain the basic