Question

Is cardinality of a relation of rdbms can be zero?

Answer 1

In the context of databases, cardinalityrefers to the uniqueness of data values contained in a column. ... It is not common, but cardinality also sometimes refers to the relationshipsbetween tables. Cardinality between tables can be one-to-one, many-to-one or many-to-many.

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Answer 2

Answer:

In SQL (Structured Query Language), the term cardinality refers to the uniqueness of data values contained in a particular column (tuple) of a database table. The lower the cardinality, the more duplicated elements in a column. Thus, a column with the lowest possible cardinality would have the same value for every row.