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Wednesday, August 7, 2019

Answer Sections 3 Quiz Database Programming with SQL 2019 Learner - English



Section 3 Quiz


Which of the following is earliest in the rules of precedence?  
                                                                               
                                               
                Arithmetic operator (*)

                                               
                Concatenation operator


                                               
                Logical condition

                                               
                Comparison condition

                                                                               
Which of the following statements best describes the rules of precedence when using SQL?                                                                        
                                               
                The order in which the columns are displayed

                                               
                The order in which the expressions are sorted

                                               
                The order in which the operators are returned

                                               
                The order in which the expressions are evaluated and calculated (*)

                                               
                All of the above

                                                                               
From left to right, what is the correct order of Precedence? 

                                               
                NOT, AND, OR, Arithmetic

                                               
                Arithmetic, Concatenation, Comparison, OR (*)

                                               
                Arithmetic, NOT, Concatenation, Logical

                                               
                Arithmetic, NOT, Logical, Comparison

                                                                               
The ORDER BY clause always comes last. True or False?
                                               
                True (*)

                                               
                False

                                                                               
Which of the following are TRUE regarding the logical AND operator?   
                                               
                TRUE AND FALSE return TRUE

                                               
                FALSE AND TRUE return NULL

                                               
                TRUE AND TRUE return FALSE

                                               
                TRUE AND FALSE return FALSE (*)

Evaluate this SQL statement:
SELECT product_id, product_name, price
FROM products
ORDER BY product_name, price;

What occurs when the statement is executed?
                                                                               
                                               
                The results are sorted numerically only.

                                               
                The results are sorted alphabetically only.

                                               
                The results are sorted alphabetically and then numerically. (*)

                                               
                The results are sorted numerically and then alphabetically.

                                                                               
Evaluate this SELECT statement:
SELECT employee_id, last_name, first_name, salary 'Yearly Salary'
FROM employees
WHERE salary IS NOT NULL
ORDER BY last_name, 3;

Which clause contains an error?
                                                                      
                                               
                ORDER BY last_name, 3;

                                               
                SELECT employee_id, last_name, first_name, salary 'Yearly Salary' (*)

                                               
                WHERE salary IS NOT NULL

                                               
                FROM employees

                                                                               
Evaluate this SELECT statement:
SELECT last_name, first_name, email
FROM employees
ORDER BY email;

If the EMAIL column contains null values, which statement is true?
                                                             
                                               
                Null email values will be displayed last in the result. (*)

                                               
                Null email values will not be displayed in the result.

                                               
                Null email values will be displayed first in the result.

                                               
                The result will not be sorted.

                                                                               
What clause must you place in a SQL statement to have your results sorted from highest to lowest salary?                                                       
                                               
                ORDER salary BY DESC

                                               
                None, the database always sorts from highest to lowest on the salary column.

                                               
                ORDER BY salary ASC

                                               
                ORDER BY salary DESC (*)

                                                                               
You query the database with this SQL statement:
SELECT price
FROM products
WHERE price IN(1, 25, 50, 250)
AND (price BETWEEN 25 AND 40 OR price > 50);

Which two values could the statement return? (Choose two.)
                                                                                 
                                               
                10

                                               
                1

                                               
                50

                                               
                250 (*)

                                               
                25 (*)

The conversion function TO_CHAR is a single row function. True or False?      
                                               
                True (*)

                                               
                False

                                                                               
Will the following statement return one row?
SELECT MAX(salary), MIN(Salary), AVG(SALARY)
FROM employees;
                                                               
                                               
                No, it is illegal. You cannot use more than one multi-row function in a SELECT statement.

                                               
                Yes, it will return the highest salary from each employee.

                                               
                Yes, it will return the highest salary, the lowest salary, and the average salary from all employees. (*)

                                               
                Yes, it will return the average salary from the employees table.

                                                                               
The PLAYERS table contains these columns:
PLAYERS TABLE:
LAST_NAME VARCHAR2 (20)
FIRST_NAME VARCHAR2 (20)
SALARY NUMBER(8,2)
TEAM_ID NUMBER(4)
MANAGER_ID NUMBER(9)
POSITION_ID NUMBER(4)

You want to display all players' names with position 6900 or greater.
You want the players names to be displayed alphabetically by last name and then by first name.
Which statement should you use to achieve the required results?
                                                           
                                               
                SELECT last_name, first_name
FROM players
WHERE position_id > 6900
ORDER BY last_name, first_name;

                                               
                SELECT last_name, first_name
FROM players
WHERE position_id >= 6900
ORDER BY last_name DESC, first_name;

                                               
                SELECT last_name, first_name
FROM players
WHERE position_id <= 6900
ORDER BY last_name, first_name;

                                               
                SELECT last_name, first_name
FROM players
WHERE position_id >= 6900
ORDER BY last_name, first_name;
(*)


 Evaluate this SQL statement:
SELECT e.employee_id, e.last_name, e.first_name, m.manager_id
FROM employees e, employees m
ORDER BY e.last_name, e.first_name
WHERE e.employee_id = m.manager_id;

This statement fails when executed. Which change will correct the problem?
                                                                               
                                               
                Include a HAVING clause.

                                               
                Reorder the clauses in the query. (*)

                                               
                Remove the table aliases in the ORDER BY clause.

                                               
                Remove the table aliases in the WHERE clause.


The PLAYERS table contains these columns:
PLAYERS TABLE:
LAST_NAME VARCHAR2 (20)
FIRST_NAME VARCHAR2 (20)
SALARY NUMBER(8,2)
TEAM_ID NUMBER(4)
MANAGER_ID NUMBER(9)
POSITION_ID NUMBER(4)

You must display the player name, team id, and salary for players whose salary is in the range from 25000 through 100000 and whose team id is in the range of 1200 through 1500. The results must be sorted by team id from lowest to highest and then further sorted by salary from highest to lowest. Which statement should you use to display the desired result?

                                                            
                                               
                SELECT last_name, first_name, team_id, salary
FROM players
WHERE salary BETWEEN 24999.99 AND 100000.01
AND team_id BETWEEN 1200 AND 1500
ORDER BY team_id DESC, salary DESC;

                                               
                SELECT last_name, first_name, team_id, salary
FROM players
WHERE salary BETWEEN 25000 AND 100000
AND team_id BETWEEN 1200 AND 1500
ORDER BY team_id, salary DESC;
(*)


                                               
                SELECT last_name, first_name, team_id, salary
FROM players
WHERE salary > 24999.99 AND salary < 100000
AND team_id BETWEEN 1200 AND 1500
ORDER BY team_id ASC, salary DESC;

                                               
                SELECT last_name, first_name, team_id, salary
FROM players
WHERE (salary > 25000 OR salary < 100000)
AND team_id BETWEEN 1200 AND 1500
ORDER BY team_id, salary;

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Final Exam Java Programming 2019 Learner - English

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