Data Warehousing
Data Warehousing, Data Marts and Data Mining
Data Marts
A data mart is a subset of an organizational data store, usually oriented to a specific purpose or major data subject, that may be distributed to support business needs. Data marts are analytical data stores designed to focus on specific business functions for a specific community within an organization. Data marts are often derived from subsets of data in a data warehouse, though in the bottom-up data warehouse design methodology the data warehouse is created from the union of organizational data marts.
Data Mart Details
Data marts are the "corner stores" of the enterprise, and each unique knowledge worker community has its own mart maintained by the divisional or departmental IS group. Some divisions may need only a single data mart if all knowledge workers in the division have similar information requirements. In other cases, a departmental IS organization will discover several distinct knowledge worker communities within a single department of a division.
Each data mart serves only its local community, and is modeled on the information needs of that community.
Reasons for creating a data mart
• Easy access to frequently needed data
• Creates collective view by a group of users
• Improves end-user response time
• Ease of creation
• Lower cost than implementing a full Data warehouse
• Potential users are more clearly defined than in a full Data warehouse
Dependent data mart
According to the Inmon school of data warehousing, a dependent data mart is a logical subset (view) or a physical subset (extract) of a larger data warehouse, isolated for one of the following reasons:
• A need for a special data model or schema: e.g., to restructure for OLAP
• Performance: to offload the data mart to a separate computer for greater efficiency or to obviate the need to manage that workload on the centralized data warehouse.
• Security: to separate an authorized data subset selectively
•
Data Marts
A data mart is a subset of an organizational data store, usually oriented to a specific purpose or major data subject, that may be distributed to support business needs. Data marts are analytical data stores designed to focus on specific business functions for a specific community within an organization. Data marts are often derived from subsets of data in a data warehouse, though in the bottom-up data warehouse design methodology the data warehouse is created from the union of organizational data marts.
Data Mart Details
Data marts are the "corner stores" of the enterprise, and each unique knowledge worker community has its own mart maintained by the divisional or departmental IS group. Some divisions may need only a single data mart if all knowledge workers in the division have similar information requirements. In other cases, a departmental IS organization will discover several distinct knowledge worker communities within a single department of a division.
Each data mart serves only its local community, and is modeled on the information needs of that community.
Reasons for creating a data mart
• Easy access to frequently needed data
• Creates collective view by a group of users
• Improves end-user response time
• Ease of creation
• Lower cost than implementing a full Data warehouse
• Potential users are more clearly defined than in a full Data warehouse
Dependent data mart
According to the Inmon school of data warehousing, a dependent data mart is a logical subset (view) or a physical subset (extract) of a larger data warehouse, isolated for one of the following reasons:
• A need for a special data model or schema: e.g., to restructure for OLAP
• Performance: to offload the data mart to a separate computer for greater efficiency or to obviate the need to manage that workload on the centralized data warehouse.
• Security: to separate an authorized data subset selectively
•