Let relation R2 has a Foreign Key that refers to Primary Key of relation R1. Which of the following operations may cause violation of referential integrity constraints?I: insert into R1II: insert into R2III: delete from R1IV: delete from R2

Let relation R2 has a Foreign Key that refers to Primary Key of relati

1.	Let relation R2 has a Foreign Key that refers to Primary Key of relation R1. Which of the following operations may cause violation of referential integrity constraints?I: insert into R1II: insert into R2III: delete from R1IV: delete from R2
A.	II and III
B.	I and IV
C.	I, II and III
D.	III and IV
Answer» B. I and IV

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Let relation R2 has a Foreign Key that refers to Primary Key of relation R1. Which of the following operations may cause violation of referential integrity constraints?I: insert into R1II: insert into R2III: delete from R1IV: delete from R2

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