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Advanced Database Technology SNS COLLEGE OF TECHNOLOGY (An Autonomous Institution) COIMBATORE – 35 DEPARTMENT OF COMPUTER SIENCE AND ENGINEERING (UG & PG) Third Year Computer Science and Engineering, 6th Semester Multiple Choice Questions Subject Code & Name: CS319 / Advanced Database Technology Prepared by: Ms.V.Savitha,AP/CSE. UNIT – I 1. An ________ is a set of entities of the same type that share the same properties, or attributes . a) Entity set b) Attribute set c) Relation set d) Entity model Answer:a 2. Entity is a a) Object of relation b) Present working model c) Thing in real world d) Model of relation Answer:c 3. The descriptive property possessed by each entity set is _________ . a) Entity b) Attribute c) Relation d) Model Answer:b 4. The function that an entity plays in a relationship is called that entity’s _____________. a) Participation b) Position c) Role SNSCT- Department of Computer Science and Engineering Page 1 Advanced Database Technology d) Instance Answer:c 5. The attribute name could be structured as a attribute consisting of first name, middle initial, and last name . This type of attribute is called a) Simple attribute b) Composite attribute c) Multivalued attribute d) Derived attribute Answer:b 6. The attribute AGE is calculated from DATE_OF_BIRTH . The attribute AGE is a) Single valued b) Multi valued c) Composite d) Derived Answer:d 7. Not applicable condition can be represented in relation entry as a) NA b) 0 c) NULL d) Blank Space Answer:c 8. Which of the following can be a multivalued attribute ? a) Phone_number b) Name c) Date_of_birth d) All of the mentioned Answer:a 9. Which of the following is a single valued attribute a) Register_number b) Address c) SUBJECT_TAKEN d) Reference Answer:a. SNSCT- Department of Computer Science and Engineering Page 2 Advanced Database Technology 10. In a relation between the entities the type and condition of the relation should be specified . That is called as______attribute a) Desciptive b) Derived c) Recursive d) Relative Answer:a 11. In the __________ normal form, a composite attribute is converted to individual attributes. A) First B) Second C) Third D) Fourth Answer:a 12. A table on the many side of a one to many or many to many relationship must: a) Be in Second Normal Form (2NF) b) Be in Third Normal Form (3NF) c) Have a single attribute key d) Have a composite key Answer:d 13. Tables in second normal form (2NF): a) Eliminate all hidden dependencies b) Eliminate the possibility of a insertion anomalies c) Have a composite key d) Have all non key fields depend on the whole primary key Answer:a 14. Which-one ofthe following statements about normal forms is FALSE? a) BCNF is stricter than 3 NF b) Lossless, dependency -preserving decomposition into 3 NF is always possible c) Loss less, dependency – preserving decomposition into BCNF is always possible d) Any relation with two attributes is BCNF Answer:c 15. Functional Dependencies are the types of constraints that are based on______ a) Key b) Key revisited c) Superset key SNSCT- Department of Computer Science and Engineering Page 3 Advanced Database Technology d) None of these Answer:a 16. Which is a bottom-up approach to database design that design by examining the relationship between attributes: a) Functional dependency b) Database modeling c) Normalization d) Decomposition Answer:c 17. Which forms simplifies and ensures that there is minimal data aggregates and repetitive groups: a) 1NF b) 2NF c) 3NF d) All of the mentioned Answer:c 18. Which forms has a relation that possesses data about an individual entity: a) 2NF b) 3NF c) 4NF d) 5NF Answer:c 19. Which forms are based on the concept of functional dependency: a) 1NF b) 2NF c) 3NF d) 4NF Answer:c 20. Empdt1(empcode, name, street, city, state,pincode). For any pincode, there is only one city and state. Also, for given street, city and state, there is just one pincode. In normalization terms, empdt1 is a relation in a) 1 NF only b) 2 NF and hence also in 1 NF c) 3NF and hence also in 2NF and 1NF SNSCT- Department of Computer Science and Engineering Page 4 Advanced Database Technology d) BCNF and hence also in 3NF, 2NF and 1NF Answer:b 21. A collection of data designed to be used by different people is called a/an a) Organization b) Database c) Relationship d) Schema Answer: b 22. Which of the following is the oldest database model? a) Relational b) Deductive c) Physical d) Network Answer: d 23. Which of the following schemas does define a view or views of the database for particular users? a) Internal schema b) Conceptual schema c) Physical schema d) External schema Answer: d 24. Which of the following is an attribute that can uniquely identify a row in a table? a) Secondary key b) Candidate key c) Foreign key d) Alternate key Answer: b 25. Which of the following is the process of selecting the data storage and data access characteristics of the database? a) Logical database design b) Physical database design c) Testing and performance tuning d) Evaluation and selecting Answer: b 26. Which of the following terms does refer to the correctness and completeness of the data in a database? a) Data security SNSCT- Department of Computer Science and Engineering Page 5 Advanced Database Technology b) Data constraint c) Data independence d) Data integrity Answer: d 27. The relationship between DEPARTMENT and EMPLOYEE is a a) One-to-one relationship b) One-to-many relationship c) Many-to-many relationship d) Many-to-one relationship Answer: b 28. A table can be logically connected to another table by defining a a) Super key b) Candidate key c) Primary key d) Unique key Answer: c 29. If the state of the database no longer reflects a real state of the world that the database is supposed to capture, then such a state is called a) Consistent state b) Parallel state c) Durable state d) Inconsistent state Answer: d 30. Ensuring isolation property is the responsibility of the a) Recovery-management component of the DBMS b) Concurrency-control component of the DBMS c) Transaction-management component of the DBMS d) Buffer management component in DBMS Answer: b 31. Consider money is transferred from (1)account-A to account-B and (2) account-B to accountA. Which of the following form a transaction ? a) Only 1 b) Only 2 c) Both 1 and 2 individually d) Either 1 or 2 SNSCT- Department of Computer Science and Engineering Page 6 Advanced Database Technology Answer:c 32. A transaction is delimited by statements (or function calls) of the form __________. a) Begin transaction and end transaction b) Start transaction and stop transaction c) Get transaction and post transaction d) Read transaction and write transaction Answer:a 33. Identify the characteristics of transactions a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:d 34. Which of the following has “all-or-none” property ? a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:a 35. The database system must take special actions to ensure that transactions operate properly without interference from concurrently executing database statements. This property is referred to as a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:c SNSCT- Department of Computer Science and Engineering Page 7 Advanced Database Technology 36. The property of transaction that persists all the crashes is a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:b 37. __________ states that only valid data will be written to the database. a) Consistency b) Atomicity c) Durability d) Isolation Answer:a 38. Transaction processing is associated with everything below except a) Producing detail summary or exception reports b) Recording a business activity c) Confirming a action or triggering a response d) Maintaining a data Answer:c 39. The Oracle RDBMS uses the ____ statement to declare a new transaction start and its properties. a) BEGIN b) SET TRANSACTION c) BEGIN TRANSACTION d) COMMIT Answer:b 40. ____ means that the data used during the execution of a transaction cannot be used by a second transaction until the first one is completed. a) Consistency SNSCT- Department of Computer Science and Engineering Page 8 Advanced Database Technology b) Atomicity c) Durability d) Isolation Answer:d 41. The method of access that uses key transformation is called as a) Direct b) Hash c) Random d) Sequential Answer: b 42. Why do we need concurrency control on B+ trees ? a) To remove the unwanted data b) To easily add the index elements c) To maintain accuracy of index d) All of the mentioned Answer: c 43. How many techniques are available to control concurrency on B+ trees? a) One b) Three c) Four d) None of the mentioned Answer: d 44. In crabbing protocol locking a) Goes down the tree and back up b) Goes up the tree and back down c) Goes down the tree and releases d) Goes up the tree and releases SNSCT- Department of Computer Science and Engineering Page 9 Advanced Database Technology Answer: a 45. The deadlock can be handled by a) Removing the nodes that are deadlocked b) Restarting the search after releasing the lock c) Restarting the search without releasing the lock d) Resuming the search Answer: b UNIT-II SNSCT- Department of Computer Science and Engineering Page 10 Advanced Database Technology 1. A distributed database has which of the following advantages over a centralized database? a) Software cost b) Software complexity c) Slow Response d). Modular growth Answer: D 2. An autonomous homogenous environment is which of the following? a) The same DBMS is at each node and each DBMS works independently. b). The same DBMS is at each node and a central DBMS coordinates database access. c) A different DBMS is at each node and each DBMS works independently. d) A different DBMS is at each node and a central DBMS coordinates database access. Answer: A 3. A transaction manager is which of the following? a) Maintains a log of transactions b). Maintains before and after database images c) Maintains appropriate concurrency control d). All of the above. Answer: Option D 4. Location transparency allows for which of the following? a). Users to treat the data as if it is at one location SNSCT- Department of Computer Science and Engineering Page 11 Advanced Database Technology b). Programmers to treat the data as if it is at one location c) Managers to treat the data as if it is at one location d) All of the above. Answer: Option D 5. A heterogeneous distributed database is which of the following? a). The same DBMS is used at each location and data are not distributed across all nodes. b). The same DBMS is used at each location and data are distributed across all nodes. c) A different DBMS is used at each location and data are not distributed across all nodes. d). A different DBMS is used at each location and data are distributed across all nodes. Answer: Option D 6. Some of the columns of a relation are at different sites is which of the following? a). Data Replication b). Horizontal Partitioning c) Vertical Partitioning d). Horizontal and Vertical Partitioning Answer: Option C 7. Which of the following is true concerning a global transaction? a) The required data are at one local site and the distributed DBMS routes requests as necessary. SNSCT- Department of Computer Science and Engineering Page 12 Advanced Database Technology b). The required data are located in at least one nonlocal site and the distributed DBMS routes requests as necessary. c) The required data are at one local site and the distributed DBMS passes the request to only the local DBMS. d) The required data are located in at least one nonlocal site and the distributed DBMS passes the request to only the local DBMS. Answer: Option B 8. A homogenous distributed database is which of the following? a) The same DBMS is used at each location and data are not distributed across all nodes. b) The same DBMS is used at each location and data are distributed across all nodes. c) A different DBMS is used at each location and data are not distributed across all nodes. d) A different DBMS is used at each location and data are distributed across all nodes. Answer: Option B 9. Replication should be used when which of the following exist? a) When transmission speeds and capacity in a network prohibit frequent refreshing of large tables. b) When using many nodes with different operating systems and DBMSs and database designs. c) The application's data can be somewhat out-of-date. d) All of the above. Answer: Option C SNSCT- Department of Computer Science and Engineering Page 13 Advanced Database Technology 10. Storing a separate copy of the database at multiple locations is which of the following? a) Data Replication b) Horizontal Partitioning c) Vertical Partitioning d) Horizontal and Vertical Partitioning Answer: Option A 11. A distributed database is which of the following? a). A single logical database that is spread to multiple locations and is interconnected by a network b) A loose collection of file that is spread to multiple locations and is interconnected by a network c) A single logical database that is limited to one location. d). A loose collection of file that is limited to one location. Answer: Option A 12. A semijoin is which of the following? a) Only the joining attributes are sent from one site to another and then all of the rows are returned. b) All of the attributes are sent from one site to another and then only the required rows are returned. c) Only the joining attributes are sent from one site to another and then only the required rows are returned. d) All of the attributes are sent from one site to another and then only the required SNSCT- Department of Computer Science and Engineering Page 14 Advanced Database Technology rows are returned. Answer: Option C 13. Which of the following is a disadvantage of replication? a). Reduced network traffic b) If the database fails at one site, a copy can be located at another site. c) Each site must have the same storage capacity. d) Each transaction may proceed without coordination across the network. Answer: Option C 14. A distributed database can use which of the following strategies? a) Totally centralized at one location and accessed by many sites b) Partially or totally replicated across sites c) Partitioned into segments at different sites d) All of the above Answer: Option D 15. Which of the following is not one of the stages in the evolution of distributed DBMS? a) Unit of work b) Remote unit of work c) Distributed unit of Work SNSCT- Department of Computer Science and Engineering Page 15 Advanced Database Technology d) Distributed request Answer: Option A 16. For select operation the ________ appear in the subscript and the ___________ argument appears in the paranthesis after the sigma. a) Predicates, relation b) Relation, Predicates c) Operation, Predicates d) Relation, Operation Answer:a 17. The ___________ operation, denoted by −, allows us to find tuples that are in one relation but are not in another. a) Union b) Set-difference c) Difference d) Intersection 18. Which is a unary operation: a) Selection operation b) Primitive operation c) Projection operation d) Generalized selection Answer:d 19. Which is a join condition contains an equality operator: a) Equijoins b) Cartesian c) Natural d) Left Answer:a 20. In precedence of set operators the expression is evaluated from a) Left to left b) Left to right c) Right to left d) From user specification Answer:b SNSCT- Department of Computer Science and Engineering Page 16 Advanced Database Technology 21. Which of the following is not outer join ? a) Left outer join b) Right outer join c) Full outer join d) All of the mentioned Answer:d 22. The assignment operator is denoted by a) -> b) <c) = d) == Answer:b 23. To include integrity constraint in a existing relation use : a) Create table b) Modify table c) Alter table d) Drop table Answer:c 24. Which of the following is not a integrity constraint ? a) Not null b) Positive c) Unique d) Check ‘predicate’ Answer:b 25. Create table Employee(Emp_id numeric not null, Name varchar(20) , dept_name varchar(20), Salary numeric unique(Emp_id,Name)); insert into Employee values(1002, Ross, CSE, 10000) insert into Employee values(1006,Ted,Finance, ); insert into Employee values(1002,Rita,Sales,20000); What will be the result of the query? a) All statements executed b) Error in create statement c) Error in insert into Employee values(1006,Ted,Finance, ); d) Error in insert into Employee values(1008,Ross,Sales,20000); Answer:d SNSCT- Department of Computer Science and Engineering Page 17 Advanced Database Technology 26. Create table Manager(ID numeric,Name varchar(20),budget numeric,Details varchar(30)); Inorder to ensure that the value of budget is non-negative which of the following should be used? a) Check(budget>0) b) Check(budget<0) c) Alter(budget>0) d) Alter(budget<0) Answer:d 27. Foreign key is the one in which the ________ of one relation is referenced in another relation. a) Foreign key b) Primary key c) References d) Check constraint Answer:b 28. Create table course (... foreign key (dept name) references department . . . ); Which of the following is used to delete the entries in the referenced table when the tuple is deleted in course table? a) Delete b) Delete cascade c) Set null d) All of the mentioned Answer:b 29. Domain constraints, functional dependency and referential integrity are special forms of _________. a) Foreign key b) Primary key c) Assertion d) Referential constraint Answer:c 30. Which of the following is the right syntax for assertion? a) Create assertion 'assertion-name' check 'predicate'; b) Create assertion check 'predicate' 'assertion-name'; c) Create assertions 'predicates'; SNSCT- Department of Computer Science and Engineering Page 18 Advanced Database Technology d) All of the mentioned Answer:a 31. Data integrity constraints are used to: a) Control who is allowed access to the data b) Ensure that duplicate records are not entered into the table c) Improve the quality of data entered for a specific property (i.e., table column) d) Prevent users from changing the values stored in the table Answer:c 32. Which of the following can be addressed by enforcing a referential integrity constraint? a) All phone numbers must include the area code b) Certain fields are required (such as the email address, or phone number) before the record is accepted c) Information on the customer must be known before anything can be sold to that customer d) When entering an order quantity, the user must input a number and not some text (i.e., 12 rather than ‘a dozen’) Answer:c 33. A __________ is a special kind of a store procedure that executes in response to certain action on the table like insertion, deletion or updation of data. a) Procedures b) Triggers c) Functions d) None of the mentioned Answer:b 34. Trigger are supported in a) Delete b) Update c) Views d) All of the mentioned Answer:c 35. The CREATE TRIGGER statement is used to create the trigger. THE _____ clause specifies the table name on which the trigger is to be attached. The ______ specifies that this is an AFTER INSERT trigger. a) for insert, on b) On, for insert c) For, insert SNSCT- Department of Computer Science and Engineering Page 19 Advanced Database Technology d) Both a and c Answer:b 36. What are the after triggers ? a) Triggers generated after a particular operation b) These triggers run after an insert, update or delete on a table c) These triggers run after an insert, views, update or delete on a table d) Both b and c Answer:b 37. The variables in the triggers are declared using a) b) @ c) / d) /@ Answer:b 38. The default extension for an Oracle SQL*Plus file is: a) .txt b) .pls c) .ora d) .sql Answer:d 39. Which of the following is NOT an Oracle-supported trigger? a) BEFORE b) DURING c) AFTER d) INSTEAD OF Answer:b 40. What are the different in triggers ? a) Define, Create b) Drop, Comment c) Insert, Update, Delete d) All of the mentioned Answer:c SNSCT- Department of Computer Science and Engineering Page 20 Advanced Database Technology UNIT-III 1. ODL supports which of the following types of association relationships? SNSCT- Department of Computer Science and Engineering Page 21 Advanced Database Technology a). Unary b) Unary and Binary c) Unary and Binary and Ternary d) Unary and Binary and Ternary and higher Answer: Option B 2. An extent is which of the following? a) A keyword that indicates that the subclass inherits from a superclass b) A keyword that indicates that the superclass inherits from a subclass c) The set of all instances of a class within a database d) Only one instance of a class within a database Answer: Option C 3. Identify the class name for the following code: ABC123 course(); a) ABC123 b) course c) course() d) All of the above. Answer: Option A 4. Using ODL, you can define which of the following? SNSCT- Department of Computer Science and Engineering Page 22 Advanced Database Technology a) Attribute b) Structure c) Operation d) All of the above. Answer: Option D 5. The keyword "inverse" is used in which of the following? a) Class b) Attribute c) Relationship d) All of the above. Answer: Option C 6. The object definition language (ODL) is which of the following? a) Used to develop logical schemas b) A data definition language for OODB c) A method to implement a logical schema d) All of the above. Answer: Option D 7. An atomic literal is which of the following? SNSCT- Department of Computer Science and Engineering Page 23 Advanced Database Technology a) Strings b) Boolean c) Long d) All of the above. Answer: Option D 8. Which of the following is true concerning an ODBMS? a) They have the ability to store complex data types on the Web. b) They are overtaking RDBMS for all applications. c) They are most useful for traditional, two-dimensional database table applications. d) All of the above. Answer: Option A 9. The reserved word enum is used for which of the following? a) To define a range for an attribute. b) To define a range for a class. c) To define a range for a relationship. d) All of the above. Answer: Option A SNSCT- Department of Computer Science and Engineering Page 24 Advanced Database Technology 10. Which of the following is an unordered collection of elements that may contain duplicates? a) Set b) Bag c) List d) Dictionary Answer: Option B 11. Which of the following is true concerning the following statement: class Manager extends Employee a) Manager is a concrete class and a superclass. b) Manager is a concrete class and a subclass. c) Manager is an abstract class and a superclass. d) Manager is an abstract class and a subclass. Answer: Option B 12. Which of the following is an ordered collection of elements of the same type? a). Set b) Bag c) List d) Dictionary Answer: Option C 13. A relationship should be specified how in the ODL? a) One direction starting with the first class b) One direction starting with the second class c) Neither direction. SNSCT- Department of Computer Science and Engineering Page 25 Advanced Database Technology d) Both directions. Answer: Option D 14. Using OQL, you may do which of the following? a) Return an entire collection of elements including duplicates. b) Return a collection of elements without duplicates. c) Return a specific subset of elements using a given criteria. d) All of the above. Answer: Option D SNSCT- Department of Computer Science and Engineering Page 26 Advanced Database Technology UNIT-IV 1. Consider money is transferred from (1)account-A to account-B and (2) account-B to accountA. Which of the following form a transaction ? a) Only 1 b) Only 2 c) Both 1 and 2 individually d) Either 1 or 2 Answer:c 2. A transaction is delimited by statements (or function calls) of the form __________. a) Begin transaction and end transaction b) Start transaction and stop transaction c) Get transaction and post transaction d) Read transaction and write transaction Answer:a 3. Identify the characteristics of transactions a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:d 4. Which of the following has “all-or-none” property ? a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:a SNSCT- Department of Computer Science and Engineering Page 27 Advanced Database Technology 5. The database system must take special actions to ensure that transactions operate properly without interference from concurrently executing database statements. This property is referred to as a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:c 6. The property of transaction that persists all the crashes is a) Atomicity b) Durability c) Isolation d) All of the mentioned Answer:b 7. __________ states that only valid data will be written to the database. a) Consistency b) Atomicity c) Durability d) Isolation Answer:a 8. Transaction processing is associated with everything below except a) Producing detail summary or exception reports b) Recording a business activity c) Confirming a action or triggering a response d) Maintaining a data Answer:c 9. The Oracle RDBMS uses the ____ statement to declare a new transaction start and its properties. SNSCT- Department of Computer Science and Engineering Page 28 Advanced Database Technology a) BEGIN b) SET TRANSACTION c) BEGIN TRANSACTION d) COMMIT Answer:b 10. ____ means that the data used during the execution of a transaction cannot be used by a second transaction until the first one is completed. a) Consistency b) Atomicity c) Durability d) Isolation Answer:d 11. The method of access that uses key transformation is called as a) Direct b) Hash c) Random d) Sequential Answer: b 12. Why do we need concurrency control on B+ trees ? a) To remove the unwanted data b) To easily add the index elements c) To maintain accuracy of index d) All of the mentioned Answer: c 13. How many techniques are available to control concurrency on B+ trees? a) One b) Three c) Four SNSCT- Department of Computer Science and Engineering Page 29 Advanced Database Technology d) None of the mentioned Answer: d 14. In crabbing protocol locking a) Goes down the tree and back up b) Goes up the tree and back down c) Goes down the tree and releases d) Goes up the tree and releases Answer: a 15. The deadlock can be handled by a) Removing the nodes that are deadlocked b) Restarting the search after releasing the lock c) Restarting the search without releasing the lock d) Resuming the search Answer: b 16. In crabbing protocol the the lock obtained on the root node is in _________ mode. a) Shared b) Exclusive c) Read only d) None of the mentioned Answer: a 17. If needed to split a node or coalesce it with its siblings, or redistribute key values between siblings, the crabbing protocol locks the parent of the node in ____________ mode. a) Shared b) Exclusive c) Read only d) None of the mentioned SNSCT- Department of Computer Science and Engineering Page 30 Advanced Database Technology Answer: b 18. In crabbing protocol to inset or delete a key value the leaf node has to be locked in ___________ mode. a) Shared b) Exclusive c) Read only d) None of the mentioned Answer: b 19. B-link tree requires a pointer to its __________ sibling. a) Upper b) Lower c) Right d) Left Answer: c 21 Instead of locking index leaf nodes in a two-phase manner, some index concurrency-control schemes use ___________ on individual key values, allowing other key values to be inserted or deleted from the same leaf. a) B+ tree locking b) Link level locking c) Key-value locking d) Next value locking Answer: c 22. The log is a sequence of ___________, recording all the update activities in the database. a) Log records b) Records c) Entries d) Redo Answer: a SNSCT- Department of Computer Science and Engineering Page 31 Advanced Database Technology 23. In the ___________ scheme, a transaction that wants to update the database first creates a complete copy of the database. a) Shadow copy b) Shadow Paging c) Update log records d) All of the mentioned Answer: a 24. The ____________ scheme uses a page table containing pointers to all pages; the page table itself and all updated pages are copied to a new location. a) Shadow copy b) Shadow Paging c) Update log records d) All of the mentioned Answer: b 25. The current copy of the database is identified by a pointer, called _____________, which is stored on disk. a) Db-pointer b) Update log c) Update log records d) All of the mentioned Answer: a 26. If a transaction does not modify the database until it has committed, it is said to use the ___________ technique. a) Deferred-modification b) Late-modification c) Immediate-modification d) Undo Answer: a SNSCT- Department of Computer Science and Engineering Page 32 Advanced Database Technology 27. If database modifications occur while the transaction is still active, the transaction is said to use the ___________technique. a) Deferred-modification b) Late-modification c) Immediate-modification d) Undo Answer: c 28. ____________ using a log record sets the data item specified in the log record to the old value. a) Deferred-modification b) Late-modification c) Immediate-modification d) Undo Answer: d 29. In the __________ phase, the system replays updates of all transactions by scanning the log forward from the last checkpoint. a) Repeating b) Redo c) Replay d) Undo Answer: b 30. The actions which are played in the order while recording it is called ______________ history. a) Repeating b) Redo c) Replay d) Undo Answer: a 41. A special redo-only log record is written to the log, where V1 is the value being restored to data item Xj during the rollback. These log records are sometimes called a) Log records b) Records SNSCT- Department of Computer Science and Engineering Page 33 Advanced Database Technology c) Compensation log records d) Compensation redo records Answer: c UNIT –V 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. The following technology is not well-suited for data mining: A.Expert system technology B.Data visualization C.Technology limited to specific data types such as numeric data types D.Parallel architecture SNSCT- Department of Computer Science and Engineering Page 34 Advanced Database Technology Ans: c 5. 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 6. The value at the intersection of the row labeled "India" and the column "Savings" in Table2 should be: A.800,000 B.300,000 C.200,000 D.300,000 Ans: a 7. We want to add the following capabilities to Table2: show the data for 3 age groups (20-39, 40-60, over 60), 3 revenue groups (less than $10,000, $10,000-$30,000, over $30,000) and add a new type of account: Money market. The total number of measures will be: A.4 B.More than 100 C.Between 10 and 30 (boundaries includeD. D.Between 40 and 60 (boundaries includeD. Ans: b 8. We want to add the following capability to Table2: for each type of account in each region, also show the dollar amount besides the number of customers. This adds to Table2: A.Another dimension B.Other column(s) C.Other row(s) D.Another measure for each cell Ans: d 9. 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 10. 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 SNSCT- Department of Computer Science and Engineering Page 35 Advanced Database Technology 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 11. 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 12. 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 13. The generic two-level data warehouse architecture includes which of the following? A. At least one data mart B. Data that can extracted from numerous internal and external sources C. Near real-time updates D. All of the above. Ans: B 14. The @active data warehouse architecture includes which of the following? A. At least one data mart B. Data that can extracted from numerous internal and external sources C. Near real-time updates D. All of the above. Ans: D 15. Reconciled data is which of the following? A. Data stored in the various operational systems throughout the organization. B. Current data intended to be the single source for all decision support systems. C. Data stored in one operational system in the organization. D. Data that has been selected and formatted for end-user support applications. Ans: B SNSCT- Department of Computer Science and Engineering Page 36 Advanced Database Technology 16. Transient data is which of the following? A. Data in which changes to existing records cause the previous version of the records to be eliminated B. Data in which changes to existing records do not cause the previous version of the records to be eliminated C. Data that are never altered or deleted once they have been added D. Data that are never deleted once they have been added Ans: A 17. The extract process is which of the following? A. Capturing all of the data contained in various operational systems B. Capturing a subset of the data contained in various operational systems C. Capturing all of the data contained in various decision support systems D. Capturing a subset of the data contained in various decision support systems Ans: B 18. Data scrubbing is which of the following? A. A process to reject data from the data warehouse and to create the necessary indexes B. A process to load the data in the data warehouse and to create the necessary indexes C. A process to upgrade the quality of data after it is moved into a data warehouse D. A process to upgrade the quality of data before it is moved into a data warehouse Ans: D 19. The load and index is which of the following? A. A process to reject data from the data warehouse and to create the necessary indexes B. A process to load the data in the data warehouse and to create the necessary indexes C. A process to upgrade the quality of data after it is moved into a data warehouse D. A process to upgrade the quality of data before it is moved into a data warehouse Ans: B 20. 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 21. Data scrubbing is which of the following? A.A process to reject data from the data warehouse and to create the necessary indexes B. A process to load the data in the data warehouse and to create the necessary indexes C. A process to upgrade the quality of data after it is moved into a data warehouse D.A process to upgrade the quality of data before it is moved into a data warehouse Ans:D 22. The @active data warehouse architecture includes which of the following? SNSCT- Department of Computer Science and Engineering Page 37 Advanced Database Technology A.At least one data mart B. Data that can extracted from numerous internal and external sources C. Near real-time updates D.All of the above. Ans:D 23. A goal of data mining includes which of the following? A. To explain some observed event or condition B. To confirm that data exists C. To analyze data for expected relationships D.To create a new data warehouse Ans:A 24. 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 25.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 26.A snowflake schema is which of the following types of tables? A.Fact B. Dimension C. Helper D.All of the above Ans:D 27.The generic two-level data warehouse architecture includes which of the following? A.At least one data mart B. Data that can extracted from numerous internal and external sources C. Near real-time updates D.All of the above. Ans:B 28.Fact tables are which of the following? A.Completely denormalized SNSCT- Department of Computer Science and Engineering Page 38 Advanced Database Technology B. Partially denoralized C. Completely normalized D.Partially normalized Ans:C 29. 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 30.Reconciled data is which of the following? A.Data stored in the various operational systems throughout the organization. B. Current data intended to be the single source for all decision support systems. C. Data stored in one operational system in the organization. D.Data that has been selected and formatted for end-user support applications. Ans:B 31. The load and index is which of the following? A.A process to reject data from the data warehouse and to create the necessary indexes B. A process to load the data in the data warehouse and to create the necessary indexes C. A process to upgrade the quality of data after it is moved into a data warehouse D.A process to upgrade the quality of data before it is moved into a data warehouse Ans:B 32. The extract process is which of the following? A.Capturing all of the data contained in various operational systems B. Capturing a subset of the data contained in various operational systems C. Capturing all of the data contained in various decision support systems D.Capturing a subset of the data contained in various decision support systems Ans:B 33.A star schema has what type of relationship between a dimension and fact table? A.Many-to-many B. One-to-one C. One-to-many D.All of the above. Ans:C 34.Transient data is which of the following? SNSCT- Department of Computer Science and Engineering Page 39 Advanced Database Technology A.Data in which changes to existing records cause the previous version of the records to be eliminated B. Data in which changes to existing records do not cause the previous version of the records to be eliminated C. Data that are never altered or deleted once they have been added D.Data that are never deleted once they have been added Ans:A 35.A multifield transformation does which of the following? A.Converts data from one field into multiple fields B. Converts data from multiple fields into one field C. Converts data from multiple fields into multiple fields D.All of the above Ans:D SNSCT- Department of Computer Science and Engineering Page 40