In concurrency control policy the lock is obtained on

Related MCQs

• The situation where the lock waits only for a specified amount of time for another lock to be released is
• A(n) ____ lock exists when concurrent transactions are granted Read access on the basis of a common lock.
• In a ____ lock, the DBMS will lock an entire disk page.
• Assume transaction A holds a shared lock R. If transaction B also requests for a shared lock on R.
• A concurrency-control policy such as this one leads to              performance since it forces transactions to wait for preceding transactions to finish before they can start.
• Why do we need concurrency control on B+ trees ?
• How many techniques are available to control concurrency on B+ trees?
• Instead of locking index leaf nodes in a two-phase manner, some index concurrency- control schemes use                        on individual key values, allowing other key values to be inserted or deleted from the same leaf.
• Concurrency control is important for which of the following reasons?
• In crabbing protocol, the lock obtained on the root node is in                    mode.