Describe Referential Integrity ?

Describe Referential Integrity ?
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1 Answer

Answer :

A rule defined on a column (or set of columns) in one table that allows
the insert or update of a row only if the value for the column or set of
columns (the dependent value) matches a value in a column of a
related table (the referenced value). It also specifies the type of data
manipulation allowed on referenced data and the action to be
performed on dependent data as a result of any action on referenced
data.
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