UNIT-I 1. Which of the following features usually applies to data in a data warehouse? A.Data are often deleted B.Most applications consist of transactions C.Data are rarely deleted D.Relatively few records are processed by applications Ans: c 2. Which of the following statement is true? A.The data warehouse consists of data marts and operational data B.The data warehouse is used as a source for the operational data C.The operational data are used as a source for the data warehouse D.All of the above Ans: c 3. The following is true of three-tier data warehouses: A.Once created, the data marts will keep on being updated from the data warehouse at periodic times B.Once created, the data marts will directly receive their new data from the operational databases C.The data marts are different groups of tables in the data warehouse D.A data mart becomes a data warehouse when it reaches a critical size Ans: a 4. What is true of the multidimensional model? A.It typically requires less disk storage B.It typically requires more disk storage C.Typical business queries requiring aggregate functions take more time D.Increasing the size of a dimension is difficult Ans: b 5. The most common source of change data in refreshing a data warehouse is: A.Queryable change data B.Cooperative change data C.Logged change data D.Snapshot change data Ans: d 6. Which of the following statements is not true about refreshing a data warehouse: A.It is a process of managing timing differences between the updating of data sources and the related data warehouse objects B.Updates to dimension tables may occur at different times than the fact table C.The data warehouse administrator has more control over the load time lag than the valid time lag D.None of the above Ans: d 7. A data warehouse is which of the following? A. Can be updated by end users. B. Contains numerous naming conventions and formats. C. Organized around important subject areas. D. Contains only current data. Ans: C 8. An operational system is which of the following? A. A system that is used to run the business in real time and is based on historical data. B. A system that is used to run the business in real time and is based on current data. C. A system that is used to support decision making and is based on current data. D. A system that is used to support decision making and is based on historical data. Ans: B
9. Data transformation includes which of the following? A. A process to change data from a detailed level to a summary level B. A process to change data from a summary level to a detailed level C. Joining data from one source into various sources of data D. Separating data from one source into various sources of data Ans: A 10. A snowflake schema is which of the following types of tables?
A. B. C. D.
Fact Dimension Helper All of the above Ans:D 11. Fact tables are which of the following? A. Completely denoralized B. Partially denoralized C. Completely normalized D. Partially normalized Ans:C 12. To represent any n–Dimension data we need a series of _______ Dimension cubes. A.(n–1) B.n C.n+1 D.n+2 Ans:A 13. Data about data is called _____________. A Table B Database C Metadata D Integration Ans:C 14. Which of the following is the most important when deciding on the data structure of a data mart? (a) XML data exchange standards (b) Data access tools to be used (c) Metadata naming conventions (d) Extract, Transform, and Load (ETL) tool to be used (e) All (a), (b), (c) and (d) above. Ans: B Data access tools to be used when deciding on the data structure of a data mart 15. The process of removing the deficiencies and loopholes in the data is called as (a) Aggregation of data (b) Extracting of data (c) Cleaning up of data. (d) Loading of data (e) Compression of data.
Ans: C The process of removing the deficiencies and loopholes in the data is called as cleaning up of data. 16. At which level we can create dimensional models? (a) Business requirements level (b) Architecture models level (c) Detailed models level (d) Implementation level (e) Testing level. Ans: B Dimensional models can be created at Architecture models level 17. Which of the following is not related to dimension table attributes? (a) Verbose (b) Descriptive (c) Equally unavailable (d) Complete (e) Indexed. Ans: C Equally unavailable is not related to dimension table attributes 18. Data warehouse bus matrix is a combination of (a) Dimensions and data marts (b) Dimensions and facts (c) Facts and data marts (d) Dimensions and detailed facts (e) All (a), (b), (c) and (d) above. Ans: A Data warehouse bus matrix is a combination of Dimensions and data marts 19. Data modeling technique used for data marts is (a) Dimensional modeling (b) ER – model (c) Extended ER – model (d) Physical model (e) Logical model Ans: A Data modeling technique used for data marts is Dimensional modeling. 20. A warehouse architect is trying to determine what data must be included in the warehouse. A meeting has been arranged with a business analyst to understand the data requirements, which of the following should be included in the agenda? (a) Number of users (b) Corporate objectives (c) Database design (d) Routine reporting (e) Budget. Ans: D Routine reporting should be included in the agenda. 21. Which of the following statements is true? (a) A fact table describes the transactions stored in a DWH (b) A fact table describes the granularity of data held in a DWH
(c) The fact table of a data warehouse is the main store of descriptions of the transactions stored in a DWH (d) The fact table of a data warehouse is the main store of all of the recorded transactions over time (e) A fact table maintains the old records of the database. Ans: D The fact table of a data warehouse is the main store of all of the recorded transactions over time is the correct statement. 22. Most common kind of queries in a data warehouse (a) Inside-out queries (b) Outside-in queries (c) Browse queries (d) Range queries (e) All (a), (b), (c) and (d) above. Ans: A The Most common kind of queries in a data warehouse is Inside-out queries. 23. Which of following form the set of data created to support a specific short lived business situation? (a) Personal data marts (b) Application models (c) Downstream systems (d) Disposable data marts (e) Data mining models. Ans: D Disposable Data Marts is the form the set of data created to support a specific short lived business situation. 24. What is/are the different types of Meta data? I. Administrative. II. Business. III. Operational. (a) Only (I) above (b) Both (II) and (III) above (c) Both (I) and (II) above (d) Both (I) and (III) above (e) All (I), (II) and (III) above. Ans: E The different types of Meta data are Administrative, Business and Operational 25. Which of the following should not be considered for each dimension attribute? (a) Attribute name (b) Rapid changing dimension policy (c) Attribute definition (d) Sample data (e) Cardinality. Ans: B Rapid changing dimension policy should not be considered for each dimension attribute
26. A Business Intelligence system requires data from: (a) Data warehouse (b) Operational systems (c) All possible sources within the organization and possibly from external sources (d) Web servers (e) Database servers Ans: A A business Intelligence system requires data from Data warehouse 27. In a data warehouse, if D1 and D2 are two conformed dimensions, then (a) D1 may be an exact replica of D2 (b) D1 may be at a rolled up level of granularity compared to D2 (c) Columns of D1 may be a subset of D2 and vice versa (d) Rows of D1 may be a subset of D2 and vice versa (e) All (a), (b), (c) and (d) above. Ans: . A In a data warehouse, if D1 and D2 are two conformed dimensions, then D1 may be an exact replica of D2. 28. Which of the following schema contains multiple fact tables? A.Star schema B.Snowflake schema C.Fact constellation D.None of the above Ans:C 29. ____________ is used to refer to systems and technologies that provide the business with the means for decision makers to extract personalized meaningful information about their business and industry. A.Business intelligence B.Data warehouse C.Data base D.All the above Ans:A 30. ________ can be used to help avoid errors in schema integration. A User data B System administrator C Metadata D All the above Ans:C
