What are the main reasons for introducing the concepts of superclasses and subclasses into an ER model?
What will be an ideal response?
There are two important reasons for introducing the concepts of superclasses and subclasses
into an ER model. Firstly, it avoids describing similar concepts more than once, thereby
saving time for the designer and making the ER diagram more readable. Secondly, it adds
more semantic information to the design in a form that is familiar to many people. For
example, the assertions that ‘Manager IS-A member of staff’ and ‘flat IS-A type of property’,
communicates significant semantic content in a concise form
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Fill in the blank(s) with the appropriate word(s).
How can an administrator test an MSA to ensure that it can access the domain with its current credentials, or can be installed on a member computer?
A. By logging into the account and using it for the desired purpose B. By using the "Run MSA Test" button under service properties C. By using the Test-ADServiceAccount cmdlet D. By using the dcdiag command
Which backup medium is typically used by Linux administrators because of their price to capacity ratio?
A. tape drive B. writable DVDs C. removable hard drives D. magneto-optical drives
Which of the following network devices filters traffic of many different protocols based on a predetermined set of rules established by a system administrator?
A. Proxy B. Switch C. Firewall D. Router