Q&A Hero

Q: The information stored in the ____ is used by the DBMS for a recovery requirement triggered by a ROLLBACK statement, a program's abnormal termination, or a system failure such as a network discrepancy or a disk crash.a. data dictionary b. metadata c. rollback managerd. transaction log

Q: The implicit beginning of a transaction is ____. a. when the database is started b. when a table is accessed for the first time c. when the first SQL statement is encountered d. when the COMMIT command is issued

Q: ANSI defines four events that signal the end of a transaction. Of the following events, which is defined by ANSI as being equivalent to a ROLLBACK? a. Five SQL statements are executed. b. The end of a program is successfully reached. c. The program is abnormally terminated. d. The database is shut down for maintenance.

Q: ANSI defines four events that signal the end of a transaction. Of the following events, which is defined by ANSI as being equivalent to a COMMIT? a. Five SQL statements are executed. b. The end of a program is successfully reached. c. The program is abnormally terminated. d. The database is shut down for maintenance.

Q: The ANSI has defined standards that govern SQL database transactions. Transaction support is provided by two SQL statements: ____ and ROLLBACK.a. RETRIEVE b. ASSIGN c. UPDATEd. COMMIT

Q: A single-user database system automatically ensures ____ of the database, because only one transaction is executed at a time.a. serializability and durability b. atomicity and isolation c. serializability and isolationd. atomicity and serializability

Q: All transactions must display ____. a. atomicity, consistency, and durability b. durability and isolation c. consistency, durability, and isolation d. atomicity, durability, consistency, and isolation

Q: ____ means that data used during the execution of a transaction cannot be used by a second transaction until the first one is completed.a. Serializability b. Atomicity c. Isolationd. Time stamping

Q: ____ requires that all operations of a transaction be completed.a. Specificity b. Atomicity c. Durabilityd. Time stamping

Q: A consistent database state is ____. a. one in which all tables have foreign keys b. one in which all data integrity constraints are satisfied c. one in which all tables are normalized d. one in which all SQL statements only update one table at a time

Q: A transaction is a ____ unit of work that must be either entirely completed or aborted.a. timed b. practical c. logicald. physical

Q: The last step in the write-through technique recovery procedure is to identify the last checkpoint in the transaction log.

Q: The transaction recovery write-ahead-log protocol ensures that transaction logs are always written before any database data are actually updated.

Q: When using an optimistic approach, during the write phase, the transaction is validated to ensure that the changes made will not affect the integrity and consistency of the database.

Q: An optimistic approach is based on the assumption that the majority of the database operations do not conflict.

Q: When using an optimistic approach, a transaction reads the database, executes the needed computations, and makes the updates to a private copy of the database values.

Q: A growing phase in a two-phase lock is when a transaction acquires all the required locks without locking any data.

Q: A field-level lock allows concurrent transactions to access the same row, as long as they require the use of different fields within that row.

Q: A shared lock produces no conflict as long as all the concurrent transactions are read-write only.

Q: In a page-level lock, the DBMS will lock an entire diskpage.

Q: The scheduler establishes the order in which the operations within concurrent transactions are executed.

Q: The phenomenon of uncommitted dataoccurs when two transactions are executed concurrently and the first transaction is rolled back after the second transaction has already accessed the uncommitted datathus violating the isolation property of transactions.

Q: Durability requires that all portions of the transaction must be treated as a single, logical unit of work in which all operations are applied and completed to produce a consistent database.

Q: The multiuser DBMS must implement controls to ensure serializability and isolation of transactions, in addition to atomicity and durability, in order to guard the database's consistency and integrity.

Q: Incomplete or improper transactions can have a devastating effect on database integrity.

Q: Serializability means that data used during the execution of a transaction cannot be used by a second transaction until the first one is completed.

Q: Atomicity indicates the permanence of the database's consistent state.

Q: The DBMS guarantees that the semantic meaning of a transaction truly represents the real-world event.

Q: Although the DBMS is designed to recover a database to a previous consistent state when an interruption prevents the completion of a required set of transactions, the transactions themselves are defined by the end user or programmer and must be semantically correct.

Q: To ensure consistency of the database, every transaction must begin with the database in an unstable state.

Q: Most real-world database transactions are formed by only one database request.

Q: At the level of middle management, the database must be able to ____. a. represent and support the company operations as closely as possible b. deliver the data necessary for tactical decisions and planning c. produce query results within specified performance levels d. provide access to external and internal data to identify growth opportunities and to chart the direction of such growth

Q: A DBMS facilitates ____. a. interpretation and presentation of data in useful formats b. destruction of data and information to the right people at the right time c. data presentation and data usage monitoring for adequate periods of time d. automatic auditing of all data changes

Q: The DBA can use an audit log to automatically record a brief description of the database operations performed by the users.

Q: Database access can be controlled by placing limits on the use of the DBMS's query and reporting tools.

Q: The DBA must define data views to protect and control the scope of the data that are accessible to an authorized user.

Q: Protecting the data in the database is a function of authorization management.

Q: Security breaches can yield a database whose integrity is either preserved or corrupted.

Q: The maintenance activities of the DBA are an extension of the operational activities.

Q: Training people to use the DBMS and its tools is not included in the DBA's technical activities.

Q: The allocation of storage resources is determined when the DBMS is created.

Q: System support activities cover all tasks directly related to the day-to-day operations of a DBMS and its applications.

Q: Testing procedures and standards must already be in place before any application program can be approved for use in the company.

Q: The end user must provide testing and evaluation services for all the database and DBA applications.

Q: The DBA works with managers to ensure the quality and integrity of database design and transactions.

Q: The DBA function provides data modeling and design services to the end-user community, often through coordination with an application development group within the data-processing department.

Q: The DBA must supervise the installation of all software and hardware designated to support the data administration strategy, must have a thorough understanding of the components being installed, and must be familiar with the installation, configuration, and startup procedures of such components.

Q: The end user's role requires a broad understanding of DBMS functions, configuration, programming languages, data modeling and design methodologies, and so on.

Q: The DBA is responsible for ensuring that the data are distributed to the right persons, at the right time, and in the right format.

Q: The DBA or security officer must secure an insurance policy to provide financial protection in the event of a database failure.

Q: Physical protection of hardware and software must be accomplished by the use of open installations with restricted area access.

Q: The storage locations for multiple backups must include sites inside and outside the organization.

Q: Backups must be clearly identified through detailed descriptions and date information, assuring that the correct backup is used to recover the database.

Q: Concurrent backups take place while the user is working on the database.

Q: Incremental backups produce a backup of all data.

Q: A full backup, or database dump, produces a complete copy of the entire database.

Q: Disaster management includes all the end-user activities designed to secure data availability following a physical disaster or a database integrity failure.

Q: The security, privacy, and integrity of the data in the database are of minimal concern to DBAs who manage current DBMS installations.

Q: The DBA interacts with the end user by providing data and information support services to the organization's departments.

Q: The introduction of a DBMS represents a big change and challenge, and is likely to have a profound impact throughout the organization.

Q: Having a computerized DBMS guarantees that the data will be properly used to provide the best solutions required by managers.

Q: An enterprise database can be defined as the company's data representation that provides support for all present and expected future operations.

Q: The DBMS must provide tools that give each level of management a different view of the data and support the required level of decision-making.

Q: The testing and evaluation of a database application cover all aspects of the systemfrom the simple collection and creation of data to its use and retirement. What is covered by the evaluation process?

Q: Describe the need for convenient and safe backup storage.

Q: Explain conflict and problem resolution as part of the DBA's end-user support services.

Q: Explain user requirements gathering as part of the DBA's end-user support services.

Q: Describe the DBA's managerial role.

Q: A(n) ____________________physically stores the database's data.

Q: By default, Oracle automatically creates ____________________ and SYS user IDs that have administrative privileges with every new database you create.

Q: A(n) ________________________________________ provides a framework that includes the use of computerized, automated, and integrated tools such as a DBMS and CASE tools.

Q: One CASE tool, ____________________ Data Modeler by Computer Associates, produces fully documented ER diagrams that can be displayed at different abstraction levels.

Q: In the IBM DB2 system catalog tables, ____________________ stores one row for each column of each table or view.

Q: An access ____________________ describes the type of authorized access.

Q: A security ____________________is a weakness in a system component that could be exploited to allow unauthorized access or cause service disruptions.

Q: ____________________ focuses on maintaining the data free of inconsistencies and anomalies.

Q: The DBA must periodically generate a(n) ____________________ report to determine whether there have been actual or attempted security violationsand, if so, from what locations, and if possible, by whom.

Q: Performance monitoring and ____________________ require much of the DBA's attention and time. These activities are designed to ensure that the DBMS, utilities, and applications maintain satisfactory performance levels.

Q: The DBA must review the database application design to ensure that transactions are ____________________, meaning that they do not overload the DBMS.

Q: The selection of the DBMS ____________________ involves asking the question, "Are the company's needs better served by a relational, object-oriented, or object/relational DBMS?"