Let for any relation R. IR represents operation insert into R and DR represents operation delete from R. Assume that a relation R2 has a foreign key that refers to primary key of another relation R1. Two operations that may cause violation of referential integrity constraints are:

Let for any relation R. IR represents operation insert into R and DR r

1.	Let for any relation R. IR represents operation insert into R and DR represents operation delete from R. Assume that a relation R2 has a foreign key that refers to primary key of another relation R1. Two operations that may cause violation of referential integrity constraints are:
A.	IR1 and IR2
B.	DR1 and DR2
C.	IR1 and DR2
D.	IR2 and DR1
Answer» E.

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Let for any relation R. IR represents operation insert into R and DR represents operation delete from R. Assume that a relation R2 has a foreign key that refers to primary key of another relation R1. Two operations that may cause violation of referential integrity constraints are:

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