8.Entity attributes are represented as A. fields. B. files. C. records. D. table
ID: 665896 • Letter: 8
Question
8.Entity attributes are represented as
A. fields.
B. files.
C. records.
D. tables.
9.Which is NOT true of validation rules?
A They enforce a size limit.
B They check authenticity of data entered in a field.
C An error message will appear if a rule is violated.
D They protect from fraudulent practices.
10.All of the following are examples of primary keys EXCEPT
A employee ID.
B social security number.
C ISBN number on a textbook.
D last name.
Explanation / Answer
8.Entity attributes are represented as A.fields (or columns)
An attribute is nothing but a characteristic of an entity object or view object, implemented as a software data base property of the object class. An attribute can correspond to a database column, or be independent of a column or field.
9.Which is NOT true of validation rules?
D They protect from fraudulent practices. - This is not true because usually the attackers (cyber criminals) will make sure the fradulent data entered perfectly meets out all the data integrity checks, syntax and format rules, exact pattern matching etc. For example, some criminal wants to steal money from another's bank account by doing an internet funds transfer to his/her account. They will first do a research to find out the exact number of digits that make up your bank account number, the BSB (Bank State Branch) code, exact spelling of the account details etc. Hence they will not make any mistakes in the data - hence the validation rules can not spot those cyber criminals hence validation rules are not enough to stop fradulent practices. You need firewalls, data encryption, public key , private key encryption, ciphering etc to stop the frauds.
10.All of the following are examples of primary keys EXCEPT D last name
This is obvious because primary key means some field(or column) that is unique. Last name can not be unique. For example, there may be many persons with the same last name especially if they are from the same family - like John South, Cameron South, Charlie South and Elizabeth South. Now all these 4 people are having the same last name South - hence we can not uniquely identify a single person using last name as the primary key. Hence last name can not be used as a primary key. But all other 3 fields like employee ID, Social security number and ISBN of a book are unique - no duplicates - hence they can be used as primary key. So the answer is last name is not an axample of primary key.
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