An operation is said to be                      if executing it several times in a row gives the same result as executing it once.

Related MCQs

• 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
• The          lock allows concurrent transactions to access the same row as long as they require the use of different fields within that row.
• The ____ lock allows concurrent transactions to access the same row as long as they require the use of different fields within that row.
•                          allows individual row operation to be performed on a given result set or on the generated by a selected by a selected statement.
• Which lock should be obtained to prevent a concurrent transaction from executing a conflicting read, insert or delete operation on the same key value.
• Which of the following trigger is executed once for each row in a transaction?
• There are “record-once” versions of the compact disk and digital video disk, which can be written only once; such disks are also called                      disks.
• Let us consider phone_number ,which can take single or several values . Treating phone_numberas an                    permits instructors to have several phone numbers (including zero) associated with them.
• Let us consider phone_number ,which can take single or several values . Treating phone_numberasan _________ permits instructors to have several phone numbers (including zero) associated with them.
• Statement 1: A tuple is a row in a relation Statement 2: Existence of multiple foreign keys in a same relation is possible