What is referential integrity and how is it achieved?
Answer / koteshwar rao .palleboina
when foreign key constraint is created on a column
referential integrity is achieved .
when foreign key constraint is created on a column,that
column reference other column in the different table or
even in the same table but the reference column must be
primary key or unique key.
when a new value is added in a column referenced with
foreign key ,then the foreign key relation checks whether
the new value matches with the reference column or not.
If value matches then they are allowed into the table
Is This Answer Correct ? | 15 Yes | 1 No |
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