Managing Multiuser Databases The advantage of optimistic locking is that: the lock is obtained before the transaction has processed. the lock never needs to be obtained. transactions that are best suited are those with a lot of activity. the lock is obtained only after the transaction has processed. the lock is obtained before the transaction has processed. the lock never needs to be obtained. transactions that are best suited are those with a lot of activity. the lock is obtained only after the transaction has processed. ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Which of the following occurs when one transaction reads a changed record that has not been committed to the database? Nonrepeatable read Consistent read Dirty read Phantom read Nonrepeatable read Consistent read Dirty read Phantom read ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Which of the following occurs when a transaction rereads data it has previously read and finds modification or deletions caused by a committed transaction? Consistent read Dirty read Nonrepeatable read Phantom read Consistent read Dirty read Nonrepeatable read Phantom read ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Dirty read, nonrepeatable, and phantom reads are not possible in this instance. Repeatable read Read committed Serializable Read uncommitted Repeatable read Read committed Serializable Read uncommitted ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases A durable transaction is one in which all committed changes are permanent. True False True False ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases The goal of database security is to ensure that only authorized users can perform authorized activities at authorized times. True False True False ANSWER DOWNLOAD EXAMIANS APP