Managing Multiuser Databases Locks placed by command are implicit locks. False True False True ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Which of the following disallows both dirty reads and nonrepeatable reads, but allows phantom reads? Repeatable read Read committed Read uncommitted Serializable Repeatable read Read committed Read uncommitted Serializable ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases The size of a lock is called: lock granularity exclusive lock implicit lock shared lock lock granularity exclusive lock implicit lock shared lock 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
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 The advantage of optimistic locking is that: transactions that are best suited are those with a lot of activity. the lock never needs to be obtained. the lock is obtained only after the transaction has processed. the lock is obtained before the transaction has processed. transactions that are best suited are those with a lot of activity. the lock never needs to be obtained. the lock is obtained only after the transaction has processed. the lock is obtained before the transaction has processed. ANSWER DOWNLOAD EXAMIANS APP