FAQ's on Relational Database System

Relational Database Management System Q1.Which of the following is database element? (a) Data (b) Constraints and schema (c) relationships (d) all of these Q2.What separates the physical aspects of data storage from the logical aspects of data representation? (a) Data (b) schema (c) constraints (d) relationships Q3.What schema defines how and where the data are organized in a physical data storage? (a) external (b) internal (c) conceptual (d) none of these Q4.What is the RDBMS terminology for a row? (a) tuple (b) relation (c) attribute (d) domain Q5.Which of the following Keys in a table can uniquely identify a row in a table? (a) primary key (b) alternate key (c) candidate key (d) all of these Q6.A table can have only one? (a) primary key (b) alternate key (c )candidate key (d) all of these Q7.What is a set of possible data values called? (a) degree (b) attribute (c) domain (d) tuple Q8. What are all candidate Keys,other than the primary keys called? (a) secondary keys (b) alternate key (c) eligible keys (d) none of these Q9.What is the name of attribute or attribute combination of one relation whose values are required To match those of the primary key of some other relation? (a) candidate key (b) primary key (c) foreign key (d) matching key Q10. What is the smallest unit of data in the relational model? (a) data type (b) field (c) data value (d) none of these Q11. Codd’s Formulation rule states that: (a) a relational database management system must manage the database entirely through its relational capabilities. (b) null values are systematically supported independent of data type. (c) all information is represented logically by values in tables. (d) none of these. Q12. Which of the following is not a data definition statement? (a) INDEX (b) CREATE (c) MODIFY (d) DELETE Q13. Which of the following statements is used to create a table? (a) CREATE TABLE (b) MAKE TABLE (c) CONSTRUCT TABLE (d) None of these Q14. Which of the following is the result of a SELECT statement? (a) TRIGGER (b) INDEX (c) TABLE (d) none of these Q15. The SQL data definition language (DDL) provides commands for: (a) defining relational schemas (b) deleting relations (c) modifying relation schemas (d) all of these Q16. Which of the following is a clause in SELECT statement? (a) GROUP BY and HAVING (b) ORDER BY (c) WHERE (d) all of these Q17. Which of the following is used to get all the coloumns of a table? (a) * (b) @ (c) % (d) # Q18. Which of the following clause is usually used together with aggregate functions? (a) ORDER BY ASC (b) GROUP BY (c) ORDER BY DESC (d) none of these Q19. SELECT operation of SQL is a: (a) data query language (b) data definition language (c) data manipulation language (d) data control language Q20. Which of the following is not a DML statement? (a) UPDATE (b) COMMIT (c) INSERT (d) DELETE Q21. Which of the following is not a DDL statement? (a) ALTER (b) DROP (c) CREATE (d) SELECT Q22. What will be the result of statement such as SELECT * FROM EMPLOYEE WHERE SALARY IN (4000,8000)? (a) all employees whose salary is either 4000 or 8000 (b) all employees whose salary is between 4000 and 8000 (c) all employees whose salary is not between 4000 and 8000 (d) none of these Q23. An association among three entities called: (a) binary relationship (b) ternary relationship (c) recursive relationsh (d) none of these Q24. What are the components of E-R model ? (a) entity (b) attribute (c) relationship (d) all of these Q25. The SQL Expression Select distinct T.branchname from branch T,branch S where T.assets>S.assets and S.branchcity = “NOIDA” finds names of (a) all branches that have greater assets than some branch located in NOIDA. (b) all branches that have greater assets than all branch located in NOIDA. (c) the branch that has the greatest asset in NOIDA. (d) any branch that has greater asset than any branch located in NOIDA. Q26. Normalization is a process of (a) decomposing a set of relations. (b) successive reduction of relation schema. (c) deciding which attributes in a relation to be grouped together. (d) all of theses. Q27. A relation R is said to be in 3NF if the (a) relation R is in 2NF (b) nonprime attributes are mutually independent (c) functionally dependent on the primary key. (d) all of these. Q28. The expansion of BCNF is (a) Boyd – Codd Normal form (b) Boyce – Ccromwell Normal form (c) Boyce – Codd Normal form (d) none of these Q29. The fourth normal form is concerned with dependencies between the elements of compound keys composed of (a) one attribute (b) two attributes (c) three or more attributes (d) none of these Q30. A trigger is (a) a statement that enables to start any DBMS (b) a statement that is executed by the user when debugging an application program (c) a condition the system tests for the validity of the database user. (d) a statement that is executed automatically by the system as a side effect of a modification to the Database. Q31. Relations produced from an E-R model will always be in (a) first normal form (b) second normal form (c) third normal form (d) fourth normal form Q32. Consider the Join of a relation R with a relation S.If R has m tuples and S has n tuples, than the maximum and minimum sizes of the join respectively are: (a) m+n and 0 (b) mn and 0 (c) m+n and m-n (d) mn and m+n Q33. Functional Dependencies are a generalization of (a) key dependencies (b) relation dependencies (c) database dependencies (d) none Q34. Every BCNF decomposition is (a) dependency preserving (b) not dependency preserving (c) need be dependency preserving (d) none Q35 If we declare A ISA B then (a) every A entity is considered as B entity (b) every B entity is considered as A entity (c) either a) or b) may occur (d) none Q36. Which of the following levels of abstraction involves the views of data? (a)external level (b)conceptual level (c)physical level (d)none Q37. Relational operator that yields all possible pairs of rows from two tables is known as (a)union (b)product (c)join (d)project Q38 Referential integrity dictates that: (a) the value of a primary key must appear in a foreign key of the related table. (b) the value of a foreign key must appear in a primary key of the related table. (c) the value of a primary key cannot appear in a foreign key of the related table. (d) the value of a foreign key cannot appear in a primary key of the related table. Q39 Which of the following is not a valid aggregate function? (a) COUNT (b) COMPUTE (c) SUM (d) MAX Q40 A table that is in 2NF and contains no transitive dependencies is said to be in (a) 1NF (b) 2NF. (c) 3NF (d) 4NF NOTE: SOLUTION OF THESE DBMS QUESTIONS WILL BE UPDATED SOONLY....