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 Phantom read Dirty read Nonrepeatable read Consistent read Phantom read Dirty read Nonrepeatable read ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Resource locking is a process to prevent multiple applications from obtaining copies of the same record when the record is about to be changed. True False True False ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases Locks placed by the DBMS are called ________ . shared locks exclusive locks explicit locks implicit locks shared locks exclusive locks explicit locks implicit locks ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases The transaction log contains a copy of every database record (or page) after it has changed. These records are called before images. True False True False ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases A transaction in which either all of the database actions occur or none of them do is called: durable. isolated. atomic. consistent. durable. isolated. atomic. consistent. ANSWER DOWNLOAD EXAMIANS APP
Managing Multiuser Databases 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. True False True False ANSWER DOWNLOAD EXAMIANS APP