A phantom read occurs when a transaction rereads data it has previously read and finds modifications or deletions caused by a committed transaction.
A phantom read occurs when a transaction rereads data it has previously read and finds modifications or deletions caused by a committed transaction.
Which of the following locks the item from access of any type?
Which of the following locks the item from access of any type?
Which of the following occurs when one transaction reads a changed record that has not been committed to the database?
Which of the following occurs when one transaction reads a changed record that has not been committed to the database?
The transaction log contains a copy of every database record (or page) after it has changed. These records are called before images.
The transaction log contains a copy of every database record (or page) after it has changed. These records are called before images.
The size of the lock is referred to as the lock granularity.
The size of the lock is referred to as the lock granularity.
A transaction is a series of actions to be taken on the database so that either all of them are performed successfully or none of them are performed at all.
A transaction is a series of actions to be taken on the database so that either all of them are performed successfully or none of them are performed at all.
A transaction for which all committed changes are permanent is called:
A transaction for which all committed changes are permanent is called:
When one transaction reads a changed record that has not been committed to the database a filthy read occurs.
When one transaction reads a changed record that has not been committed to the database a filthy read occurs.
Locks placed by command are called ________ .
Locks placed by command are called ________ .
Which of the following occurs when a transaction rereads data and finds new rows that were inserted by a command transaction since the prior read?
Which of the following occurs when a transaction rereads data and finds new rows that were inserted by a command transaction since the prior read?
A cursor type in which the application can only move forward through the recordset is called:
A cursor type in which the application can only move forward through the recordset is called:
In this instance, dirty reads are disallowed, while nonrepeatable reads and phantom reads are allowed.
In this instance, dirty reads are disallowed, while nonrepeatable reads and phantom reads are allowed.
Which of the following disallows both dirty reads and nonrepeatable reads, but allows phantom reads?
Which of the following disallows both dirty reads and nonrepeatable reads, but allows phantom reads?
A durable transaction is one in which all committed changes are permanent.
A durable transaction is one in which all committed changes are permanent.
What is the overall responsibility of the DBA?
What is the overall responsibility of the DBA?
The overall responsibility of the DBA is to facilitate the development and use of the database.
The overall responsibility of the DBA is to facilitate the development and use of the database.
A cursor type in which the application sees the data as they were at the time the cursor was opened is called:
A cursor type in which the application sees the data as they were at the time the cursor was opened is called:
A point of synchronization between the database and the transaction log is generally referred to as a stop point.
A point of synchronization between the database and the transaction log is generally referred to as a stop point.
An ACID transaction is one that is atomic, consistent isolated, and durable.
An ACID transaction is one that is atomic, consistent isolated, and durable.
Which of the following allows dirty reads, nonrepeatable reads and phantom reads to occur?
Which of the following allows dirty reads, nonrepeatable reads and phantom reads to occur?
A transaction in which either all of the database actions occur or none of them do is called:
A transaction in which either all of the database actions occur or none of them do is called:
Locks placed by command are implicit locks.
Locks placed by command are implicit locks.
Locks placed by the DBMS are called ________ .
Locks placed by the DBMS are called ________ .
Resource locking is a process to prevent multiple applications from obtaining copies of the same record when the record is about to be changed.
Resource locking is a process to prevent multiple applications from obtaining copies of the same record when the record is about to be changed.
Which of the following refers to a cursor type where changes of any type and from any source are visible?
Which of the following refers to a cursor type where changes of any type and from any source are visible?
Two transactions that run concurrently and generate results that are consistent with the results that would have occurred if they had run separately are referred to as serializable transactions.
Two transactions that run concurrently and generate results that are consistent with the results that would have occurred if they had run separately are referred to as serializable transactions.
The size of a lock is referred to as lock sizing.
The size of a lock is referred to as lock sizing.
Dirty read, nonrepeatable, and phantom reads are not possible in this instance.
Dirty read, nonrepeatable, and phantom reads are not possible in this instance.
The goal of database security is to ensure that only authorized users can perform authorized activities at authorized times.
The goal of database security is to ensure that only authorized users can perform authorized activities at authorized times.
The advantage of optimistic locking is that:
The advantage of optimistic locking is that:
When two transactions are being processed against the database at the same time they are termed concurrent transactions.
When two transactions are being processed against the database at the same time they are termed concurrent transactions.
An exclusive lock locks the item from change but not from read.
An exclusive lock locks the item from change but not from read.
The lost update problem is when User A reads data that have been processed by a portion of a transaction from User B.
The lost update problem is when User A reads data that have been processed by a portion of a transaction from User B.
Locks placed by the DBMS are explicit locks.
Locks placed by the DBMS are explicit locks.
In optimistic locking, the assumption is made that conflict will occur.
In optimistic locking, the assumption is made that conflict will occur.
The size of a lock is called:
The size of a lock is called:
Which of the following occurs when a transaction rereads data it has previously read and finds modification or deletions caused by a committed transaction?
Which of the following occurs when a transaction rereads data it has previously read and finds modification or deletions caused by a committed transaction?
Database administration refers to a function that applies to the entire organization.
Database administration refers to a function that applies to the entire organization.
Which of the following locks the item from change but not from read?
Which of the following locks the item from change but not from read?
Which of the following refers to a cursor type that when the cursor is opened, a primary key value is saved for each row in the recordset; when the application accesses a row, the key is used to fetch the current values of the row?
Which of the following refers to a cursor type that when the cursor is opened, a primary key value is saved for each row in the recordset; when the application accesses a row, the key is used to fetch the current values of the row?
