Basic Terminologies of DBMS.
Relation:
In a relational model, data is stored in relations. Relation is
another name of table.
Entity:
Entity is a
place, person, thing or event for which data is to be collected is called
entity.
Tuple:
Every relation or table consists of many tuples. Tuples are also
called records or rows.
Attribute or Data Element:
An attribute
is a named column of a relation. Attributes are also called characteristics.
Data Value:
The data or information that contained in data
element is called data value.
Domain:
A domain is a collection of all possible values of one or more
attributes.
Degree:
The number of attributes is called the degree of that relation.
Cardinality:
The number of rows is called the
cardinality of that relation.
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