Exam 16: Data Warehouse Technology and Management

In the data warehouse maintenance process,auditing the data to resolve any data quality problems occurs in both the preparation and integration phases.

Which one of the following applications/activities is typical of a data warehouse?

Which of the following is not an example of application of data mining?

Figure: Table1 Bank product Location Number-of-customers Checking USA 1,000,000 Checking Europe 500,000 Checking SE Asia 1,100,000 Checking India 300,000 Savings USA 700,000 Savings Europe 400,000 Savings SE Asia 900,000 Savings India 800,000 Mutual funds USA 300,000 Mutual funds Europe Mutual funds SE Asia 300,000 Mutual funds India 80,000 Table2 Location Checking Savings Mutual Funds USA 1,000,000 700,000 300,000 Europe 500,000 400,000 200,000 SE Asia 1,100,000 900,000 300,000 India The numeric values in Table2 indicate the number of customers. -We add the following two dimensions to Table2: age groups (20-39,40-60,over 60)and revenue groups (less than $10,000,$10,000-$30,000,over $30,000).The star schema consists of the following number of tables:

When N is the number of grouped columns,the result of a CUBE operation can be produced by using (2*N)- 1 additional SELECT statements connected by a UNION operator.

In refreshing a data warehouse,________________ change data involves notification from a source system,and typically occurs after a transaction is completed using a trigger.

In a(n)______________ data warehouse architecture,operational data are transformed and loaded into the data warehouse,which is accessed directly by the user departments.

ROLAP (Relational OLAP)and MOLAP (Multidimensional OLAP)are similar in that a data cube is actually built and stored for use with queries.

A(n)___________________ is a multidimensional format sometimes known as a hypercube,because conceptually it could have an infinite number of dimensions.

Data in a data warehouse is usually normalized to fourth normal form to avoid insert and update anomalies.

A(n)_______________________ is a conceptual data model of a data warehouse which defines the structure of the data warehouse and the metadata to access the operational databases and external data sources.

One of the decision support operations that can be performed on a data cube is the _______________ operation,in which one or more dimensions are set to specific values and the remaining data cube is displayed.

The _____________ operator is an extension of the SQL GROUP BY clause that produces all combinations of subtotals in addition to the normal totals.

HOLAP (Hybrid OLAP)involves both relational and multidimensional data storage,and can combine data from both of these sources for data cube operations.

Vendors of relational DBMSs have extended their products with additional features to support operations and storage structures for multidimensional data.These product extensions are collectively known as _________._________ engines support a variety of storage and optimization techniques for summary data retrieval.

In refreshing a data warehouse,________________ change data involves files that record changes or other user activity.

One of the decision support operations that can be performed on a data cube is the _______________ operation,which rearranges the dimensions in a data cube so that the data can be presented in a more visually appealing order.

Data warehouses have four distinguishing characteristics.Data warehouses are subject-oriented,integrated,time-variant,and volatile.

An oper mart is a just-in-time data mart,usually built from one operational database in anticipation or in response to major events such as disasters and new product introductions.

The two tiered data warehouse architecture incorporates data marts to provide different departments or sections of the organization with faster access while isolating them from data needed by other user groups.