Relational Model: The relational model represents the database as a collection of
relations. A relation is nothing but a table of values. Every row in the table
represents a collection of related data values. These rows in the table denote
a real-world entity or relationship.
The table
name and column names are helpful to interpret the meaning of values in each
row. The data are represented as a set of relations. In the relational model,
data are stored as tables. However, the physical storage of the data is
independent of the way the data are logically organized.
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Relations: In relational data model, relations are saved in the
format of Tables. This format stores the relation among entities. A table has
rows and columns, where rows represents records and columns represent the attributes.
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Tuple: A single row of a table, which contains a single record for
that relation is called a tuple.
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Relation instance: A finite set of tuples in the relational
database system represents relation instance. Relation instances do not have
duplicate tuples.
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Relation schema: A relation schema describes the relation name
(table name), attributes, and their names.
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Relation key: Each row has one or more attributes, known as
relation key, which can identify the row in the relation (table) uniquely.
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Attribute domain: Every attribute has some pre-defined value
scope, known as attribute domain.