Asked By
rizwan
280 points
N/A
Posted on - 06/28/2011
Hi guys Rizwan is here I am preparing my MCS notes and during studies I am facing few problem and I want to share then with
All of you may be anyone can help me in this case what is the difference between view and materialized view?
Also tell me that what is a Cube and Linked Cube with reference to data warehouse?
Thanks in advance all of you.
Answered By
B.lie
25 points
N/A
#88960
Difference between view and materialized view
Hello,
A view is created by combining data from different tables. Hence, a view does not have data of itself. On the other hand, Materialized view usually used in data warehousing has data. This data helps in decision making, performing calculations etc. The data stored by calculating it before hand using queries.
When a view is created, the data is not stored in the database. The data is created when a query is fired on the view, whereas data of a materialized view is stored. View: Tail raid data representation is provided by a view to access data from its table. It has logical structure can not occupy space.
Changes get affected in corresponding tables. Materialized view: Pre calculated data persists in materialized view. It has physical data space occupation. Changes will not get affected in corresponding tables. Cube and Linked Cube with reference ,Logical data representation of multidimensional data is depicted as a Cube. Dimension members are represented by the edge of cube and data values are represented by the body of cube. A data cube stores data in a summarized version which helps in a faster analysis of data.
Whereas linked cubes use the data cube and are stored on another analysis server. Linking different data cubes reduces the possibility of sparse data. Linked cubes are the cubes that are linked in order to make the data remain constant.
Difference between view and materialized view
View and Materialized View:
View is virtual. View runs the query definition when they are accessed.
 On the other hand materialized view is disc based. It updates periodically based on the query definition.
Cube and Linked Cube:
Cube is logical representation of multidimensional data.
Linked cube ensures that the data in the cube remains consistent.
