Q. Let R1(a, b, c) and R2(x, y, z) be two relations in which a is the foreign key of R1 that refers to the primary key of R2. Consider following four options.

(a) Insert into R1 (b) Insert into R2
(c) Delete from R1 (d) Delete from R2

Which of the following is correct about the referential integrity constraint with respect to above?

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Q. Consider a hash table of size seven, with starting index zero, and a hash function (7x+3) mod 4. Assuming the hash table is initially empty, which of the following is the contents of the table when the sequence 1, 3, 8, 10 is inserted into the table using closed hashing? Here “__” denotes an empty location in the table.

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Q. Which of the following is/are true with reference to 'view' in DBMS?

(a) A 'view' is a special stored procedure executed when certain event occurs.
(b) A 'view' is a virtual table, which occurs after executing a pre-compiled query.

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Q. In SQL, .................. is an Aggregate function.

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Q. Match the following with respect to RDBMS:

List - I
(a) Entity integrity
(b) Domain integrity
(c) Referential integrity
(d) Userdefined integrity

List - II
(i) enforces some specific business rule that do not fall into entity or domain
(ii) Rows can't be deleted which are used by other records
(iii) enforces valid entries for a column
(iv) No duplicate rows in a table

Code:
(a) (b) (c) (d)

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Q. In RDBMS, different classes of relations are created using ................... technique to prevent modification anomalies.

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Q. .................. SQL command changes one or more fields in a record.

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Q. If every non-key attribute is functionally dependent on the primary key, then the relation is in ....................

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Q. Consider a relation R (A, B, C, D, E, F, G, H), where each attribute is atomic, and following functional dependencies exist.

CH → G
A → BC
B → CFH
E → A
F → EG

The relation R is ....................

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Q. Given two relations R1(A, B) and R2(C, D), the result of following query
Select distinct A, B from R1, R2
is guaranteed to be same as R1 provided one of the following condition is satisfied.

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Q. Consider a schema R(A, B, C, D) and following functional dependencies.

A → B
B → C
C → D
D → B

Then decomposition of R into R1(A, B), R2(B, C) and R3(B, D) is ..................

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