For each of the locking implementations of the isolation levels, state whether IS locks are required and when they can be released.
What will be an ideal response?
READ UNCOMMITTED: No read locks are required and hence no intention to read locks.
READ COMMITTED: Read locks are short term, and for each short term read lock on a tuple, a short term IS lock must be obtained on the table.
REPEATABLE READ: Read locks are long term, and for each long term read lock on a
tuple, a long term IS lock must be obtained on the table.
SERIALIZABLE: If index locking is used, a long term IS lock on the table must be
acquired. If index locking is not used, an S lock is acquired on the table and no IS lock is needed.
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What will be an ideal response?
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