Q&A Hero

Q: Breaking hardware, power outages, and human mistakes are all reasons that ________.

Q: The recovery method in which we undo the changes that erroneous or partially processed transactions have made in the database is called ________ recovery.

Q: The recovery method where the database is restored using the saved data, and all transactions since the save are reapplied is called ________ recovery.

Q: Transaction results are kept in a(n) ________, which contains records of the data changes in chronological order.

Q: Standard SQL defines four ________, which specify which of the concurrency control problems are allowed to occur.

Q: Serializable transactions are created by having a(n) ________ phase, in which locks are obtained, and a(n) ________ phase, in which locks are released.

Q: Database administrators must make sure that ________ and ________ techniques and procedures are operating to protect the database in case of failure and to recover it as quickly and accurately as possible when necessary.

Q: Database administrators must make sure that ________ measures are in place and enforced so that only authorized users can take authorized actions at appropriate times.

Q: One of the major tasks of the database administration is called ________ control, which allows multiple users to access the database simultaneously.

Q: ________ is an important business function whose purpose is to manage the database to maximize its value to the organization.

Q: When Microsoft Access 2013 uses user-level security with an Access 2003 file, the database is stored in a(n): A) *.accdb file. B) *.accdc file. C) *.accde file. D) *.mdb file. E) *.mdw file.

Q: When Microsoft Access 2013 creates a signed package with a digital signature, the database file will be a(n): A) *.accdb file. B) *.accdc file. C) *.accde file. D) *.mdb file. E) *.mdw file.

Q: When Microsoft Access 2013 compiles VBA code in a database, the database file will be a(n): A) *.accdb file. B) *.accdc file. C) *.accde file. D) *.mdb file. E) *.mdw file.

Q: When Microsoft Access 2013 secures a database with just a password, the database file will be a(n): A) *.accdb file. B) *.accdc file. C) *.accde file. D) *.mdb file. E) *.mdw file.

Q: When Microsoft Access 2013 secures a database just by storing the database in a trusted location, the database file will be a(n): A) *.accdb file. B) *.accdc file. C) *.accde file. D) *.mdb file. E) *.mdw file.

Q: Computer systems fail for which of the following reasons? A) Hardware breaks. B) Electrical power fails. C) Programs have bugs. D) People make mistakes. E) All of the above

Q: Additional DBA responsibilities include: A) problem and error reporting. B) requests of changes to existing systems. C) controlling database configuration. D) maintaining appropriate documentation. E) All of the above

Q: A point of synchronization between the database and the transaction log is called a(n): A) before-image. B) after-image. C) recovery. D) checkpoint. E) None of the above

Q: The recovery technique in which the database is returned to a known state and then all valid transactions are reapplied to the database is known as: A) reprocessing. B) rollback. C) transaction logging. D) rollforward. E) checkpointing.

Q: Which of the following is not true of database recovery through reprocessing? A) Reprocessing makes use of a database save. B) Reprocessing takes the same amount of time as did processing in the first place. C) Reprocessing will always return the database to its exact previous state. D) Reprocessing requires a record of all transactions since the last time the database was saved. E) All of the above are true of reprocessing.

Q: What is the least restrictive isolation level that will prevent nonrepeatable reads? A) Read Committed B) Serializable C) Read Uncommitted D) Atomic Read E) Repeatable Read

Q: What is the least restrictive isolation level that will prevent dirty reads? A) Read Committed B) Serializable C) Read Uncommitted D) Atomic Read E) Repeatable Read

Q: What is the least restrictive isolation level that will prevent phantom read problems? A) Read Committed B) Serializable C) Read Uncommitted D) Atomic Read E) Repeatable Read

Q: Ensuring that each SQL statement independently processes consistent rows is known as: A) transaction level consistency. B) independent consistency. C) statement level consistency. D) process level consistency. E) serializable consistency.

Q: An ACID transaction is one that is: A) atomic. B) consistent. C) isolated. D) durable. E) All of the above

Q: Which type of lock assumes that no conflicts will occur? A) Optimistic locks B) Granular locks C) Explicit locks D) Shared locks E) Open locks

Q: Which of the following is true about a shared lock? A) It is more restrictive than an implicit lock. B) It allows only two transactions to update a record simultaneously. C) It locks the item from all access. D) It allows reads to the locked item. E) It must use a two-phase locking scheme.

Q: Whether a lock applies to data at the record level, page level, table level, or database level is referred to as: A) lock exclusivity. B) lock sharing. C) lock phasing. D) serializable locking. E) lock granularity.

Q: Preventing multiple applications from obtaining copies of the same record when the record is about to be changed is called: A) serialized reading. B) lost updating. C) concurrent processing. D) resource locking. E) block factoring.

Q: What concurrent processing problem occurs when a transaction reads a changed record that has not been committed to the database? A) Nonrepeatable reads B) Phantom reads C) Dirty reads D) Serialized reads E) Unlocked reads

Q: What concurrent processing problem occurs when a transaction rereads data and finds new rows that were inserted by a different transaction since the prior read? A) Nonrepeatable reads B) Phantom reads C) Dirty reads D) Serialized reads E) Unlocked reads

Q: When a transaction functions in such a way that either all of the transaction actions are completed or none of them will be, the transaction is said to be: A) consistent. B) isolated. C) atomic. D) locked. E) logical.

Q: The purpose of concurrency control is to: A) ensure that each form has a corresponding report. B) ensure that ASPs do not duplicate JSPs. C) ensure that one user's work does not interfere with another's. D) ensure that stored procedures do not invoke triggers. E) ensure that triggers do not invoke stored procedures.

Q: Which of the following is not a means of processing databases? A) Internet applications using ASP B) Internet applications using JSP C) Applications invoking stored procedures D) Programs coded in C# E) All of the above are means of processing a database.

Q: The term DBA refers to the: A) database accessor. B) database auditor. C) data business auditor. D) database administrator. E) data business administrator.

Q: When Microsoft Access 2013 uses user-level security with an Access 2003 file, the database is stored in a(n) *.accdb file.

Q: Microsoft Access 2013 databases can be secured by deploying databases packaged with digital signatures.

Q: Microsoft Access 2013 databases cannot be secured by password encryption.

Q: Microsoft Access 2013 databases can be secured using trusted locations for database storage.

Q: Microsoft Access 2013 uses a user-level security system.

Q: Transactions should be written to the log before they are applied to the database itself.

Q: Rollback requires the use of logs, but rollforward does not.

Q: In comparison to reprocessing, rollforward does not involve the application programs.

Q: The simplest and most feasible means of recovering a database is through reprocessing.

Q: In terms of database security, a user can be assigned many roles, and a role can be assigned to many users.

Q: Database security is easy to achieve since all security is handled by the DBMS, which is a single point of entry into the database.

Q: Generally, the more restrictive the transaction isolation level, the less the throughput of database processing.

Q: Statement level consistency means that all statements within a transaction will access consistent rows across the lifetime of the entire transaction.

Q: One advantage of optimistic locking is that the lock is obtained only after the transaction is processed.

Q: With optimistic locking, locks are first issued, then the transaction is processed, and then the locks are released.

Q: Two-phase locking can be used to ensure that transactions are serializable.

Q: Lock granularity refers to whether a lock is placed by the DBMS automatically or is placed by a command from the application program.

Q: One way to prevent concurrent processing problems is to lock data that are retrieved for update.

Q: A dirty read is a problem with concurrent processing when a transaction rereads data it has already read and finds modifications or deletions caused by another transaction.

Q: Concurrent processing of a database only poses problems when two or more processes attempt to use the same data.

Q: A transaction in which all steps must be completed successfully or none of them will be completed is called a durable transaction.

Q: All actions in an atomic transaction are completed successfully or none of the actions are completed at all.

Q: The purpose of concurrency control is to ensure that one user's work does not inappropriately influence another user's work.

Q: The acronym DBA refers to either the office or the manager.

Q: Only large database systems have a need for database administration.

Q: How are 1:1, 1:N and N:M relationships handled in Microsoft Access?

Q: How are one-to-one recursive relationships addressed using the relational model?

Q: Write the schema to represent the entities below, including tables, the proper placement of the foreign key, and referential integrity constraint.

Q: What is an association relationship, and how does it differ from an N:M relationship?

Q: Explain the representation of a many-to-many strong entity relationship in a relational database design.

Q: Explain the representation of a one-to-many strong entity relationship in a relational database design.

Q: Explain the representation of ID-dependent weak entities using the relational model.

Q: What is denormalization and why can it be desirable?

Q: Explain the pragmatic reason for using surrogate keys.

Q: Explain the process of representing an entity using the relational model.

Q: After a 1:1 relationship has been created between two tables in Microsoft Access, the Relationship Type of One-To-One appears in the ________.

Q: To create a 1:1 relationship between two tables in Microsoft Access, the Indexed property of the foreign key column must be set to ________.

Q: By default, when Microsoft Access creates a relationship between two tables it creates a(n) ________ relationship.

Q: As far as Microsoft Access is concerned, there are no ________.

Q: Microsoft Access does not create N:M relationships because Microsoft Access creates databases based on ________.

Q: A(n) ________ is a relationship among entities of the same class.

Q: For a(n) ________ weak entity, it is necessary to add the key of the parent entity to the weak entity's relation so that this added attribute becomes part of the weak entity's key.

Q: To represent a many-to-many relationship in the relational model, a(n) ________ table is used.

Q: To normalize a relation, the determinant of every functional dependency should be a(n) ________.

Q: There are cases where it is possible to normalize a table too far, in which case there may be a need for ________.