COMPUTER SCIENCE AND ENGINEERING
SQL
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
degree
|
|
|
cardinality
|
|
|
domain
|
|
|
table
|
Detailed explanation-1: -This value set is also called domain. The domain of an attribute is the collection of all possible values an attribute can have. The value set specifies the set of values that may be assigned for each individual entity. For example, we can specify the value set for designation attribute as <“PM”, “Assit”, “DM”, “SE”>.
Detailed explanation-2: -Values of an attribute are all from the same domain; • Each tuple is distinct; there are no duplicate tuples; • The order of attributes has no significance; The order of tuples has no significance.
Detailed explanation-3: -For each attribute of a relation, there is a set of permitted values, called the of that attribute. Explanation: The values of the attribute should be present in the domain. Domain is a set of values permitted.
Detailed explanation-4: -Coded Value and Range Domains. A coded value domain allows you to choose from a list of values that are allowed in a field. A range domain allows you to specify a valid range for values in a numeric field. Both types of attribute domain thus provide means of enforcing data integrity.