using a log record sets the data item specified in the log record to the old value.

Related MCQs

• A special redo-only log record < Ti, Xj, V1> is written to the log, where V1 is the value being restored to data item Xj during the rollback. These log records are sometimes called
• In a                clustering index, the index record contains the search-key value and a pointer to the first data record with that search-key value and the rest of the records will be in the sequential pointers.
• In a _______ clustering index, the index record contains the search-key value and a pointer to the first data record with that search-key value and the rest of the records will be in the sequential pointers.
• Writing the buffered log to                      is sometimes referred to as a log force.
• Whenever an update operation occurs on a page, the operation stores the LSN of its log record in the                field of the page.
• A transaction commits as soon as its commit log record is written to stable storage at the primary site. This is
• A transaction commits as soon as its commit log record is written to stable storage at the primary and the backup site. This is
• If only the primary is active, the transaction is allowed to commit as soon as its commit log record is written to stable storage at the primary site. This is
• Consider the employee work-team example, and assume that certain employees participate in more than one work team. A given employee may therefore appear in more than one of the team entity sets that are lower level entity sets of employee. Thus, the generalization is                            
• Once the lower-level lock is released, the operation cannot be undone by using the old values of updated data items, and must instead be undone by executing a compensating operation; such an operation is called