Top 1000+ Solved DataBase Management System (DBMS) MCQ Questions Answer
Q. Which of the following database object does not physically exist?
a. Base table
b. Index
c. View
d. None of the above
Q. How many tables can be joined to create a view?
a. 1
b. 2
c. Database dependent
d. None of the above
Q. Which of the following is a structure that provides faster access to the rows of a tablebased on the values of one or more columns?
a. Table
b. View
c. Index
d. None of the above
Q. Which of the following index is made up of more than one column?
a. Composite index
b. Clustered index
c. Simple index
d. None of the above
Q. Which of the following index can occur only one per table?
a. Distinct index
b. Unique index
c. Simple index
d. Clustered index
Q. Which question corresponds best to the following query?SELECT CID, CDUR - 1,' = PRICE' FROM COURSES ORDER BY 2
a. Select three columns from the COURSES table, of which the third one has a constantvalue, i.e. “ = PRICE”. Leave an empty line after every second line.
b. Select two columns from the COURSES table, the second one gets as title “ =PRICE”.Sort the data according to the second column, in ascending order.
c. Select three columns from the COURSES table, of which the third one has a constantvalue, i.e. “ = PRICE”. Sort the data according to the second column, in ascending order.
d. Select two columns from the COURSES table, of which the second one has a constantvalue, i.e. “ = PRICE”. Sort the data according to the second column, in ascending order
Q. What is the default order of Order by clause?
a. Descending
b. Ascending
c. Random
d. None of the above
Q. View the Exhibit and examine the structure of the EMPLOYEES andDEPARTMENTS tables. Which SET operator would you use in the blank space in the following SQL statement to list the departments where all the employees have managers? SELECT department_id FROM departments ____ SELECT department_id FROM employees WHERE manager_id IS NULL;
a. UNION
b. MINUS
c. INTERSECT
d. UNION ALL
Q. View the Exhibit and examine the data in the EMPLOYEES tables. Evaluate the following SQL statement: SELECT employee_id, department_id FROM employees WHERE department_id= 50 ORDER BY department_id UNION SELECT employee_id, department_id FROM employees WHERE department_id= 90 UNION SELECT employee_id, department_id FROM employees WHERE department_id= 10; What would be the outcome of the above SQL statement?
a. The statement would execute successfully and display all the rows in the ascending order ofDEPARTMENT_ID.
b. The statement would execute successfully but it will ignore the ORDER BY clause and display the rows in random order.
c. The statement would not execute because the positional notation instead of the column name should be used with the ORDER BY clause.
d. The statement would not execute because the ORDER BY clause should appear only at the end of the SQL statement, that is, in the last SELECT statement.
Q. Which CREATE TABLE statement is valid?
a. CREATE TABLE ord_details (ord_no NUMBER(2) PRIMARY KEY, item_no NUMBER(3) PRIMARY KEY, ord_date date NOT NULL); 50
b. CREATE TABLE ord_details (ord_no NUMBER(2) UNIQUE, NOT NULL, item_no NUMBER(3), ord_date date DEFAULT SYSDATE NOT NULL);
c. CREATE TABLE ord_details (ord_no NUMBER(2) , item_no NUMBER(3), ord_date date DEFAULT NOT NULL, CONSTRAINT ord_uq UNIQUE (ord_no), CONSTRAINT ord_pk PRIMARY KEY (ord_no));
d. CREATE TABLE ord_details (ord_no NUMBER(2), item_no NUMBER(3), ord_date date DEFAULT SYSDATE NOT NULL, CONSTRAINT ord_pk PRIMARY KEY (ord_no, item_no));
Q. Pick entities from the following:I. vendor II. student III. attends IV. km/hour
a. i, ii, iii
b. i, ii, iv
c. i and ii
d. iii and iv
Q. By relation cardinality we mean
a. number of items in a relationship
b. number of relationships in which an entity can appear
c. number of items in an entity
d. number of entity sets which may be related to a given entity
Q. If an entity appears in only one relationship then it is
a. a 1:1 relationship
b. a 1:N relationship
c. a N:1 relationship
d. a N:M relationship
Q. The different classes of relations created by the technique for preventing modificationanomalies are called:
a. normal forms.
b. referential integrity constraints.
c. functional dependencies.
d. None of the above is correct.
Q. A relation is in this form if it is in BCNF and has no multivalued dependencies:
a. second normal form.
b. third normal form.
c. fourth normal form.
d. domain/key normal form.