Managing Multiuser Databases The advantage of optimistic locking is that: the lock is obtained only after 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 before the transaction has processed. the lock is obtained only after 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 before the transaction has processed. ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Database administration refers to a function that applies to the entire organization. True False True False ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases 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? Phantom read Consistent read Nonrepeatable read Dirty read Phantom read Consistent read Nonrepeatable read Dirty read ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Which of the following locks the item from change but not from read? Explicit lock Shared lock Implicit lock Exclusive lock Explicit lock Shared lock Implicit lock Exclusive lock ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases A phantom read occurs when a transaction rereads data it has previously read and finds modifications or deletions caused by a committed transaction. False True False True ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Locks placed by command are called ________ . explicit locks implicit locks exclusive locks shared locks explicit locks implicit locks exclusive locks shared locks ANSWER DOWNLOAD EXAMIANS APP