(1) Web integration: The attractive features of a database system
for present scenario are ease of integration with web and mobile
applications. APIs are to be developed in line with the database
system, so that it is easy to create web pages or mobile applications
that interact with it. CouchDB is a popular database for integrating
the web and mobile applications [19].
(2) Usage of SSD: [11] using a solid-state disk (SSD) for logging
as an SSD can provide durable writes with very low latencies.
Hadoop uses SSD for the response time critical data of relatively
small size [20].
(3) Single master: Google embraced the concept of a single
master in their distributed system as a valuable tool to simplify
the design and make it more straightforward. Currently GFS uses
one master per cell [21], with multiple cells per data center. Even
though Google has worked around the issue this case underscores
the importance of scalability and the limitation of assigning different
levels of responsibility in any distributed system that is
expected to scale. The biggest weakness in this system that, the
Master can be the single point of failure. However, this can be overcome
by replicating the master state. The ‘‘Shadow Masters’’ can
provide read-only access in the absence of primary master.
(4) Overcompensated systems: CAP theorem explores tradeoffs
between Consistency, Availability, and Partition tolerance. CAP
theorem only discusses about the limitations in the face of certain
types of failures and does not constrain any system capabilities
during normal operation. CAP allows the system to guarantee
all of the ACID alongside high availability when there are no partitions
[22].
(5) Consistency versus Latency: Studies indicate that latency is a
critical factor in online interactions. Increase as small as 100 ms can
dramatically reduce the probability that customers will continue to
interact or return [23] to a web portal. In case of e-Commerce application
this is directly related to the profits. Latency can be achieved
without compensating the CAP theorem and hence it is expected
that database management systems are increasingly going to pay
more attention to decreasing the latency.