Alex Q
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Exam Quiz on Theory of database (Meirzhan), created by Alex Q on 26/03/2019.

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Theory of database (Meirzhan)

Question 1 of 81

1

A DISTINCT must always be user in the top-most SELECT statement of a set operation

Select one of the following:

  • True
  • False

Explanation

Question 2 of 81

1

A parent table referenced by a child table may not be dropped

Select one of the following:

  • True
  • False

Explanation

Question 3 of 81

1

A SELECT statement that is embedded in a clause of another SELECT statement is called

Select one of the following:

  • Main query

  • Subquery

  • Inner query

  • Outer query

Explanation

Question 4 of 81

1

A subquery must be enclosed in _________ .

Select one of the following:

  • Double quotes

  • Single quotes

  • Parantheses

  • Braces

Explanation

Question 5 of 81

1

A table can be created with or without data

Select one of the following:

  • True
  • False

Explanation

Question 6 of 81

1

Any user can grant or revoke ant type of system privileges to or from another user.

Select one of the following:

  • True
  • False

Explanation

Question 7 of 81

1

Both object and system privileges can be granted through a single role to a user.

Select one of the following:

  • True
  • False

Explanation

Question 8 of 81

1

By default, the foreign key restricts deletes of any parent row that has a corresponding child row(s).

Select one of the following:

  • True
  • False

Explanation

Question 9 of 81

1

Comparison conditions fall into two classes:

Select one of the following:

  • Single-column operators (>, \=, >\=, <, <>,<\=) and multiple-column operators (IN, ANT, ALL)

  • Single-row operators (>, \=, >\=, <, <>,<\=) and multiple-column operators (IN,ANY,ALL)

  • Single-row operators (>, \=, >\=, <, <>,<\=) and multiple-row operators (IN,ANY,ALL)

  • Multiple-row operators (>, \=, >\=, <, <>,<\=) and single-row operators (IN,ANY,ALL)

Explanation

Question 10 of 81

1

Consider the EMPLOYEES table. When condition in the WHERE clause limit the employees to IT Programmers with salary greater than 5000?

Select one of the following:

  • WHERE salary>5000 AND job_id \= 'IT_PROG'

  • WHERE salary>5000 AND job_id \= "IT_PROG"

  • WHERE salary>5000 AND job_id \= IT_PROG

  • WHERE salary>5000 OR job_id \= 'IT_PROG'

Explanation

Question 11 of 81

1

Consider the EMPLOYEES table. Which condition in the WHERE clause limit the employees to those whose salary is greater than 5000 but less than 18000?

Select one of the following:

  • WHERE salary > 5000 OR salary < 18000

  • WHERE salary < 5000 AND salary > 18000

  • WHERE salary > 5000 AND salary < 18000

  • WHERE salary >5000 AND salary > 18000

Explanation

Question 12 of 81

1

Consider the EMPLOYEES table. Which condition in the WHERE clause limit the employees to those whose last name and first name starts with the letter 'K'?

Select one of the following:

  • WHERE last_name \= 'K%' and first_name \= 'K%'

  • WHERE last_name LIKE 'K_' and first_name LIKE 'K_'

  • WHERE last_name LIKE 'K%' and first_name LIKE 'K%'

  • WHERE last_name and first_name \= 'K%'

Explanation

Question 13 of 81

1

Consider the EMPLOYEES table. Which condition in the WHERE clause limit the employees to those who do not work in the departments 90 and 60?

Select one of the following:

  • WHERE department_id \= 90 AND department_id \= 60

  • WHERE department_id IN (90,60)

  • WHERE department_id NOT IN (90,60)

  • WHERE department_id \=90 PR department_id \= 60

Explanation

Question 14 of 81

1

Consider the EMPLOYEES table. Which condition in the WHERE clause limit the employees to those who work in the department prompted by the user?

Select one of the following:

  • WHERE department_id \= '%Department'

  • WHERE department_id LIKE '%Department'

  • WHERE department_id \= '&amp;Department'

  • WHERE department_id like '_Department'

Explanation

Question 15 of 81

1

Consider the EMPLOYEES table. Which of the following statements displays the date in the 'January, 19 1998'?

Select one of the following:

  • SELECT TO_DATE(hire_date,'fmMONTH, DD YYYY') FROM employees

  • SELECT TO_DATE(hire_date,'fmMON, DD YEAR') FROM employees

  • SELECT TO_CHAR(hire_date,'fmMonth, DD YYYY') FROM employees

  • SELECT TO_DATE(hire_date,'fmMonth, DD YYYY') FROM employees

Explanation

Question 16 of 81

1

Consider the EMPLOYEES table. Which of the following conditions in the WHERE clause will generate an error?

Select one of the following:

  • SELECT * FROM employees WHERE last_name\='&amp;Name'

  • SELECT job_id, SUM(salary) FROM employees GROUP BY '&amp;Column'

  • SELECT * FROM &amp;Table

  • SELECT &amp;Column FROM employees

Explanation

Question 17 of 81

1

Consider the EMPLOYEES table. Which of the following displays the maximum average salary for each department?

Select one of the following:

  • SELECT MAX(AVG(salary)) FROM employees

  • SELECT department_id, MAX(AVG(salary)) FROM employees GROUP BY department_id

  • SELECT MAX(AVG(salary)) FROM employees GROUP BY department_id

  • SELECT AVG(MAX(salary)) FROM employees GROUP BY department_id

Explanation

Question 18 of 81

1

Consider the EMPLOYEES table. Which of the following SQL statements is correct to provide the sentence in the format "King has been working since 01.01.1987" with "Employee Information" alias?

Select one of the following:

  • SELECT last_name ||'has been working since' || hire_date "Employee Information" FROM employees;

  • SELECT last_name || 'has been working since' || hire_date Employee Information FROM employees

  • SELECT last_name || "has been working since" || hire_date "Employee Information" FROM employees;

  • SELECT last_name || 'has been working since' || hire_date 'Employee Information' FROM employees;

Explanation

Question 19 of 81

1

Consider the EMPLOYEES table. Which of the following statements count the number of employees within each department?

Select one of the following:

  • SELECT department_id, COUNT(last_name) FROM employees GROUP BY department_id

  • SELECT department_name, COUNT(last_name) FROM employees GROUP BY department_id

  • SELECT department_id, COUNT(last_name) FROM departments GROUP_BY last_name

  • SELECT department_id, department_name, COUNT(last_name) FROM employees GROUP BY department_id

Explanation

Question 20 of 81

1

Consider the following SQL statement. What will be the result? SELECT e.last_name, e.salary, d.department_name FROM employees e, departments d WHERE e.department_id \= d.department_id

Select one of the following:

  • An error will occur since none of the JOIN operations is used

  • An error will occur since in the SELECT clause a column thet is used to join the tables is missing

  • The last names of the employees and their salaries will be displayed along with the departments names where the employees work

  • The Cartesian product of the two tables based on the department_id column will be displayed

Explanation

Question 21 of 81

1

Consider the SQL statement. Which of the following clauses does not sort the result rows by the salary values in the ascending order? SELECT last_name "Employee", salary "Salary" FROM employees

Select one of the following:

  • ORDER BY salary;

  • ORDER BY 2;

  • ORDER BY "Salary" ASC;

  • ORDER BY Salary DESC;

Explanation

Question 22 of 81

1

Consider the SQL statement. Which of the following clauses does not sort the result rows by salary value in the ascending order?
SELECT last_name "Employee", salary "Salary"
FROM employees

Select one of the following:

  • ORDER BY salary;

  • ORDER BY 2;

  • ORDER BY "Salary" ASC;

  • ORDER BY Salary DESC;

Explanation

Question 23 of 81

1

Delete the zip codes 02199 and 43011 from the ZIPCODE table. Make the change permanent.

Select one of the following:

  • DELETE FROM zipcode WHERE zip ANY ('02199','43011') COMMIT

  • DELETE FROM zipcode WHERE zip ANY ('02199','43011')

  • DELETE FROM zipcode WHERE zip IN ('02199','43011') COMMIT

  • DELETE FROM zipcode WHERE zip ALL ('02199','43011') COMMIT

Explanation

Question 24 of 81

1

Constraints always have a name.

Select one of the following:

  • True
  • False

Explanation

Question 25 of 81

1

DML statement such as INSERT, UPDATE, DELETE, and MERGE obtain a lock on the row(s), so other users cannot manipulate it.

Select one of the following:

  • True
  • False

Explanation

Question 26 of 81

1

If there are schemas named USERA and USERB, and both have an EMPLOYEES table, then if USERA wants to access the EMPLOYEES table that belongs to USERB, USERA must write select statement as follows:

Select one of the following:

  • SELECT * FROM userb.employees;

  • SELECT * FROM employees;

  • SELECT * FROM usera.employees;

  • SELECT * FROM employees.userb;

Explanation

Question 27 of 81

1

It is possible to combine from two tables that do not have a primary key/foreign key relationship into one result using a set operation.

Select one of the following:

  • True
  • False

Explanation

Question 28 of 81

1

Privileges, roles, and synonyms are all used to implement security in an Oracle Database.

Select one of the following:

  • True
  • False

Explanation

Question 29 of 81

1

Queries containing set operators are called ______ .

Select one of the following:

  • Compound queries

  • Subqueries

  • Inner queries

  • Outer queries

Explanation

Question 30 of 81

1

Queries that return more than one row from the inner SELECT statement are called

Select one of the following:

  • Multiple-row subqueries

  • Multiple-column subqueries

  • Sing-column subqueries

  • Single-row subqueries

Explanation

Question 31 of 81

1

Queries that return only one row from the inner SELECT statement are called

Select one of the following:

  • Multiple-column subqueries

  • Single-row subqueries

  • Single-column subqueries

  • Multiple-row subqueries

Explanation

Question 32 of 81

1

What will be the result of the following SQL statement?
SELECT INITCAP(SUBSTR(CONCAT('Hello',world),4,3)) FROM DUAL;

Select one of the following:

  • LLO

  • Llo

  • Low

  • LOW

Explanation

Question 33 of 81

1

What will be the result of the following SQL statement?
SELECT count(d.department_name), l.city
FROM departments d NATURAL JOIN locations l
GROUP BY l.city

Select one of the following:

  • The number of department in all cities is shown

  • The number of departments in EACH city is shown.

  • An error will occur since the GROUP BY clause cannot be used with NATURAL JOIN

  • The number if departments in one particular city is shown

Explanation

Question 34 of 81

1

What will be the result of the following query?
SELECT ROUND (63.548, -1) FROM DUAL;

Select one of the following:

  • 64

  • 60

  • 63

  • 70

Explanation

Question 35 of 81

1

What will be the result of the following SQL statement?
SELECT SUBSTR ('Hello,World!!!',13) FROM DUAL

Select one of the following:

  • An error will occur, since SUBSTR function need to take 3 parameters

  • Hello,World!!!13

  • !!!

  • Hello, World!

Explanation

Question 36 of 81

1

The ______ operator compares a value to every value returned by a subquery.

Select one of the following:

  • NOT

  • ALL

  • SOME

  • ANY

Explanation

Question 37 of 81

1

The condition INSERT FIRST command evaluates the WHEN condition in order. For all conditions that are true a row is inserted into the appropriate table.

Select one of the following:

  • True
  • False

Explanation

Question 38 of 81

1

The data dictionary view USER_TAB_PRIVS_MADE lists details of table privilege grants performed by the current user.

Select one of the following:

  • True
  • False

Explanation

Question 39 of 81

1

The data of a temporary table is visible to all session.

Select one of the following:

  • True
  • False

Explanation

Question 40 of 81

1

The NUMBER data types is usually the best choice for a primary key.

Select one of the following:

  • True
  • False

Explanation

Question 41 of 81

1

The subquery generally executes ______ , and its output is used to complete the query condition for the main (or ____ ) query.{

Select one of the following:

  • First, outer

  • Last, outer

  • Last, inner

  • First, inner

Explanation

Question 42 of 81

1

The TRANCATE command and the TRUNC function can be used interchangeably.

Select one of the following:

  • True
  • False

Explanation

Question 43 of 81

1

The TRUNCATE command removes all data permanently from a table.

Select one of the following:

  • True
  • False

Explanation

Question 44 of 81

1

The UNION and UNION ALL set operator have the opposite effect other.

Select one of the following:

  • True
  • False

Explanation

Question 45 of 81

1

The ____ operator compares a value to EACH value returned by a subquery

Select one of the following:

  • NOT

  • ANY

  • SOME

  • ALL

Explanation

Question 46 of 81

1

The ____ operator returns all rows that are selected by either query

Select one of the following:

  • UNION ALL

  • INTERSECT

  • UNION

  • MINUS

Explanation

Question 47 of 81

1

The ______ constraint defines a condition that each row must satisfy.

Select one of the following:

  • PRIMARY KEY

  • CHECK

  • UNIQUE

  • FOREIGN KEY

Explanation

Question 48 of 81

1

To obtain a list of last names that students and instructors share, you use the MINUS set operator

Select one of the following:

  • True
  • False

Explanation

Question 49 of 81

1

Transaction control determines when data manipulates becomes permanent in a database.

Select one of the following:

  • True
  • False

Explanation

Question 50 of 81

1

Use the _____ operator to return all rows from multiple tables and eliminate any duplicate rows.

Select one of the following:

  • UNION

  • MINUS

  • UNION ALL

  • INTERSECT

Explanation

Question 51 of 81

1

What will be the result of the following SQL statement? (SYSDATE is a date of your exam)
SELECT TO_CHAR(SYSDATE, 'Day') FROM Dual;

Select one of the following:

  • 31.05.2013

  • Friday

  • 31

  • 31-05.2013

Explanation

Question 52 of 81

1

What will be the result of the following SQL statement? (SYSDATE is a date of your exam)
SELECT TO_CHAR(SYSDATE, 'DD.MM.YY') FROM Dual;{

Select one of the following:

  • 31.May.2013

  • An error will occur

  • 31.05.2013

  • 31.05.13

Explanation

Question 53 of 81

1

When executed, this statement cannot be rolled back

Select one of the following:

  • ALTER TABLE

  • DROP TABLE

  • REMOVE TABLE

  • DELETE TABLE

Explanation

Question 54 of 81

1

When inserting data into a table form another table, the table names and columns must be the same.

Select one of the following:

  • True
  • False

Explanation

Question 55 of 81

1

When using LIKE condition which symbol is used to denote one character?

Select one of the following:

  • _

  • +

  • %

  • *

Explanation

Question 56 of 81

1

When using LIKE conditions which symbol is used to denote zero or many characters?

Select one of the following:

  • +

  • *

  • %

  • _

Explanation

Question 57 of 81

1

Which command is used to view the structure of the table LOCATIONS?

Select one of the following:

  • DESCRIBE LOCATIONS

  • SHOW STRUCTURE LOCATIONS

  • SELECT * FROM LOCATIONS

  • PRINT LOCATIONS

Explanation

Question 58 of 81

1

Which is right of the following clauses?

Select one of the following:

  • SELECT... WHERE ... ORDER BY ... GROUP BY

  • SELECT ... FROM ... GROUP BY ... ORDER BY ... WHERE

  • SELECT...FROM...WHERE...GROUP BY...ORDER BY

  • SELECT ... FROM ... WHERE ... ORDER BY ... GROUP BY

Explanation

Question 59 of 81

1

Which keyword is used to eliminate duplicate rows in the result?

Select one of the following:

  • DISTINCT

  • DESCRIBE

  • HAVING

  • GROUP BY

Explanation

Question 60 of 81

1

Which keyword is used to provide an alias to a column?

Select one of the following:

  • COLUMN

  • AS

  • ALIAS

  • IS

Explanation

Question 61 of 81

1

Which of the following clauses is used to limit the rows that are retrieved by the query?

Select one of the following:

  • WHERE

  • ORDER BY

  • FROM

  • GROUP BY

Explanation

Question 62 of 81

1

Which of the following functions finds the numeric position of a named character?

Select one of the following:

  • CONCAT

  • INSTR

  • TRIM

  • SUBSTR

Explanation

Question 63 of 81

1

Which of the following functions is not single-row function?

Select one of the following:

  • CONCAT

  • SUM

  • UPPER

  • ROUND

Explanation

Question 64 of 81

1

Which of the following functions joins two strings together?

Select one of the following:

  • CONCAT

  • TRIM

  • INSTR

  • SUBSTR

Explanation

Question 65 of 81

1

Which of the following is a concatenation operator?

Select one of the following:

  • &amp;

  • ||

  • *

  • +

Explanation

Question 66 of 81

1

Which of the following SQL statements will generate an error?

Select one of the following:

  • SELECT last_name Name FROM employees WHERE Name like 'K%'

  • SELECT last_name Name FROM employees ORDER BY Name

  • SELECT department_id Dep, COUNT(last_name) Num FROM employees GROUP BY department_id HAVING Num>5

  • SELECT department_id Dep, COUNT(last_name) FROM employees GROUP BY dep

Explanation

Question 67 of 81

1

Which of the following statements about aliases is NOT true?

Select one of the following:

  • The keyboard AS between an alias and a column name is optional

  • Aliases always require double quotation marks

  • Aliases immediately follows the column name

  • Aliases rename column heading

Explanation

Question 68 of 81

1

Which of the following statements is NOT true?

Select one of the following:

  • SQL statements are no case sensitive

  • Keywords cannot be abbreviated

  • SQL statement can be only one line

  • Keywords cannot be split across lines

Explanation

Question 69 of 81

1

Which statement discards all pending data changes

Select one of the following:

  • SAVEPOINT

  • COMMIT

  • DISCARD

  • ROLLBACK

Explanation

Question 70 of 81

1

Which symbol do you use if you need to choose all the columns from the table to the result query?

Select one of the following:

  • %

  • All

  • +

  • *

Explanation

Question 71 of 81

1

Which symbol is used to create a substitution variable?{

Select one of the following:

  • &amp;

  • _

  • %

  • *

Explanation

Question 72 of 81

1

Write SQL statement for display the department numbers with more than employees in each dept.

Select one of the following:

  • Select deptno, count(deptno) from emp group by deptno having count(*)>3;

  • Select deptno, count(deptno) from deptno group by emp having count(*)>3;

  • Select deptno, count (emp) from deptno group by emp having count(*)>2;

  • Select deptno, count (deptno) from emp group by deptno having count(*)>2;

Explanation

Question 73 of 81

1

Write SQL statement for display the names of the employees who are working in the company for the past 5 years:

Select one of the following:

  • Select ename from emp where hiredate < add_month(sysdate,-60);

  • Select ename from emp where hiredate < add_month(sysdate,-5);

  • Select ename from emp where hiredate < add_month(sysdate,+60);

  • Select ename from emp where hiredate < add_month(sysdate,+5);

Explanation

Question 74 of 81

1

Write SQL statement for increase salary of all managers by 10%

Select one of the following:

  • Update emp set sal\=sal*1.1 where empno in (select mgr from emo);

  • Update emp set sal\=sal*0.1 where empno in (select mgr from emo);

  • Update emp set sal\=sal*0.1 where empno in (select emp from emo);

  • Update emp set sal\=sal*1.1 where empno in (select emp from emo);

Explanation

Question 75 of 81

1

You can add and drop columns from a table using the ALTER TABLE command.

Select one of the following:

  • True
  • False

Explanation

Question 76 of 81

1

You can nor (not?) selectively delete rows a table.

Select one of the following:

  • True
  • False

Explanation

Question 77 of 81

1

You can place the subquery in a number of SQL clauses, including the following:
I. WHERE clause
II. HAVING clause
III. FROM clause

Select one of the following:

  • I and II

  • I,II and III

  • I only

  • I and III

Explanation

Question 78 of 81

1

You can update only a single column at a time in a table.

Select one of the following:

  • True
  • False

Explanation

Question 79 of 81

1

You cannot drop a user if objects exist in the user's schema.

Select one of the following:

  • True
  • False

Explanation

Question 80 of 81

1

You cannot order the results of a set operation

Select one of the following:

  • True
  • False

Explanation

Question 81 of 81

1

______ clause can be used and is required in the subquery to perform Top-N analysis.

Select one of the following:

  • HAVING

  • ORDER BY

  • GROUP BY

  • WHERE

Explanation