Q1➡| NTA UGC NET June 2021 Consider following two statements: Statement I: Relational database schema represents the logical design of the database. Statement II: Current snapshot of a relation only provides the degree of the relation. In the context to the above statements, choose the correct option from the options given below:
i ➥ Both Statement I and Statement II are FALSE
ii ➥ Both Statement I and Statement II are TRUE
iii ➥ Statement I is FALSE but Statement II is TRUE
iv ➥ Statement I is TRUE but Statement II is FALSE
Q4➡| UGC NET JUNE 2019 In relational database management, which of the following is/are property/properties of candidate key? P:Uniqueness Q: Irreducibility
Q6➡| UGC NET JUNE 2019 Following table has two attributes Employee_id and Manager_id, where Employee_id is a primary key and manager_id is a foreign key referencing Employee_id with on-delete cascade:
On deleting the table (20,40), the set of other tuples that must be deleted to maintain the referential integrity of table is
Q7➡| UGC NET JUNE 2018 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 ?
i ➥ Operations (a) and (b) will cause violation.
ii ➥ Operations (b) and (c) will cause violation.
iii ➥ Operations (c) and (d) will cause violation.
Q9➡| UGC NET January 2017 Paper-II Integrity constraints ensure that changes made to the database by authorized users do not result into loss of data consistency. Which of the following statement(s) is (are) true w.r.t. the examples of integrity constraints ? (1) An instructor Id. No. cannot be null, provided Instructor Id No. being primary key. (2) No two citizens have same Adhar-Id. (3) Budget of a company must be zero.
Q10➡| UGC NET January 2017 Paper-II Let M and N be two entities in an E-R diagram with simple single value attributes. R1 and R2 are two relationship between M and N, where as R1 is one-to-many and R2 is many-to-many. The minimum number of tables required to represent M, N, R1 and R2 in the relational model are ______.
Q13➡| UGC NET July 2016 Paper-II Which of the following statement(s) is/are FALSE in the context of Relational DBMS ? I. Views in a database system are important because they help with access control by allowing users to see only a particular subset of the data in the database. II. E-R diagrams are useful to logically model concepts. III. An update anomaly is when it is not possible to store information unless some other, unrelated information is stored as well. IV. SQL is a procedural language.
