Consider hierarchic locks as illustrated in Figure 16.26. What locks must be set when an
appointment is assigned to a time-slot in week w, day d, at time, t? In what order should these locks
be set? Does the order in which they are released matter?
What locks must be set when the time slots for every day in week w are viewed?
Can this be done when the locks for assigning an appointment to a time-slot are already set?
What will be an ideal response?
Set write lock on the time-slot t, intention-to-write locks on week w and day d in week w. The locks should be
set from the top downwards (i.e. week w then day d then time t). The order in which locks are released does
matter - they should be released from the bottom up.
When week w is viewed as a whole, a read lock should be set on week w. An intention-to-write lock is already
set on week w (for assigning an appointment), the read lock must wait
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Polymorphism helps eliminate ______ logic.
What will be an ideal response?
Some networks have one or more computers, called routers, that act as the central storage location for programs and provide mass storage for most of the data used on the network.
Answer the following statement true (T) or false (F)
____ are useful is you are not familiar with computers or if you feel your computer might need replacement parts due to wear and tear.
A. Extended warranties B. Surge suppressors C. Encrypting file systems D. Optical storage technologies
Describe the purpose of creating a table of contents.
What will be an ideal response?