Pregunta 1
Pregunta
CUBE will cross-reference the columns listed in the ______ clause to create a superset of groups.
Pregunta 2
Pregunta
You use GROUPING functions to:
Respuesta
-
Produce subtotal and cross-tabulated values
-
Identify the extra row values created by either a ROLLUP or CUBE operation
-
Aggregate rows using SUM, MIN, MAX, and COUNT
Pregunta 3
Pregunta
CUBE can be applied to all aggregate functions including AVG, SUM, MIN, MAX, and COUNT. True or False?
Pregunta 4
Pregunta
GROUPING SETS is another extension to the GROUP BY clause and is used to specify multiple groupings of data but provide a single result set. True or False?
Pregunta 5
Pregunta
When using SET operators, the names of the matching columns must be identical in all of the SELECT statements used in the query. True or False?
Pregunta 6
Pregunta
When using SET operators, the number of columns and the data types of the columns must be identical in all of the SELECT statements used in the query. True or False.
Pregunta 7
Pregunta
The EMPLOYEES table contains these columns:
ID_NUMBER NUMBER Primary Key
NAME VARCHAR2 (30)
DEPARTMENT_ID NUMBER
SALARY NUMBER (7,2)
HIRE_DATE DATE
Evaluate this SQL statement:
SELECT id_number, name, department_id, SUM(salary)
FROM employees
WHERE salary > 25000
GROUP BY department_id, id_number, name
ORDER BY hire_date;
Why will this statement cause an error?
Respuesta
-
The HAVING clause is missing.
-
The WHERE clause contains a syntax error.
-
The SALARY column is NOT included in the GROUP BY clause.
-
The HIRE_DATE column is NOT included in the GROUP BY clause
Pregunta 8
Pregunta
Evaluate this SELECT statement:
SELECT SUM(salary), department_id, manager_id
FROM employees
GROUP BY department_id, manager_id;
Which SELECT clause allows you to restrict the rows returned, based on a group function?
Pregunta 9
Pregunta
The PRODUCTS table contains these columns:
PRODUCT_ID NUMBER(9) PK
CATEGORY_ID VARCHAR2(10)
LOCATION_ID NUMBER(9)
DESCRIPTION VARCHAR2(30)
COST NUMBER(7,2)
PRICE NUMBER(7,2)
QUANTITY NUMBER
You display the total of the extended costs for each product category by location.
You need to include only the products that have a price less than $25.00.
The extended cost of each item equals the quantity value multiplied by the cost value.
Which SQL statement will display the desired result?
Respuesta
-
SELECT category_id, SUM(cost * quantity) TOTAL,location_id
FROM products
WHERE price > 25.00
GROUP BY category_id, location_id;
-
SELECT SUM(cost * quantity) TOTAL, location_id
FROM products
WHERE price < 25.00
GROUP BY location_id;
-
SELECT category_id, SUM(cost * quantity) TOTAL, location_id
FROM products
WHERE price < 25.00
GROUP BY category_id, location_id;
-
SELECT SUM(cost * quantity) TOTAL
FROM products
WHERE price < 25.00
Pregunta 10
Pregunta
The PLAYERS and TEAMS tables contain these columns:
PLAYERS
PLAYER_ID NUMBER NOT NULL, PRIMARY KEY
LAST_NAME VARCHAR2 (30) NOT NULL
FIRST_NAME VARCHAR2 (25) NOT NULL
TEAM_ID NUMBER
POSITION VARCHAR2 (25)
TEAMS
TEAM_ID NUMBER NOT NULL, PRIMARY KEY
TEAM_NAME VARCHAR2 (25)
You need to create a report that lists the names of each team with more than three goal keepers.
Which SELECT statement will produce the desired result?
Respuesta
-
SELECT t.team_name, COUNT(p.player_id)
FROM players p, teams t
ON (p.team_id = t.team_id)
WHERE UPPER(p.position) = 'GOAL KEEPER'
GROUP BY t.team_name;
-
SELECT t.team_name, COUNT(p.player_id)
FROM players
JOIN teams t ON (p.team_id = t.team_id)
WHERE UPPER(p.position) = 'GOAL KEEPER'
HAVING COUNT(p.player_id) > 3;
-
SELECT t.team_name, COUNT(p.player_id)
FROM players p, teams t
ON (p.team_id = t.team_id)
WHERE UPPER(p.position) = 'GOAL KEEPER'
GROUP BY t.team_name
HAVING COUNT(p.player_id) > 3;
-
SELECT t.team_name, COUNT(p.player_id)
FROM players p
JOIN teams t ON (p.team_id = t.team_id)
WHERE UPPER(p.position) = 'GOAL KEEPER'
GROUP BY t.team_name
HAVING COUNT(p.player_id) > 3;
Pregunta 11
Pregunta
If a select list contains both a column as well as a group function then what clause is required?
Respuesta
-
HAVING clause
-
JOIN clause
-
ORDER BY clause
-
GROUP BY clause
Pregunta 12
Pregunta
The PRODUCTS table contains these columns:
PROD_ID NUMBER(4)
PROD_NAME VARCHAR(20)
PROD_CAT VARCHAR2(15)
PROD_PRICE NUMBER(5)
PROD_QTY NUMBER(4)
You need to identify the minimum product price in each product category.
Which statement could you use to accomplish this task?
Respuesta
-
SELECT prod_cat, MIN (prod_price)
FROM products
GROUP BY prod_price;
-
SELECT prod_cat, MIN (prod_price)
FROM products
GROUP BY prod_cat;
-
SELECT MIN (prod_price), prod_cat
FROM products
GROUP BY MIN (prod_price), prod_cat;
-
SELECT prod_price, MIN (prod_cat)
FROM products
GROUP BY prod_cat;
Pregunta 13
Pregunta
Group functions can be nested to a depth of?
Pregunta 14
Pregunta
What will the following SQL Statement do?
SELECT job_id, COUNT(*)
FROM employees
GROUP BY job_id;
Respuesta
-
Displays all the employees and groups them by job
-
Displays each job id and the number of people assigned to that job id
-
Displays only the number of job_ids
-
Displays all the jobs with as many people as there are jobs
Pregunta 15
Pregunta
The EMPLOYEES table contains the following columns:
EMPLOYEE_ID NUMBER(10) PRIMARY KEY
LAST_NAME VARCHAR2(20)
FIRST_NAME VARCHAR2(20)
DEPARTMENT VARCHAR2(20)
HIRE_DATE DATE
SALARY NUMBER(10)
You want to create a report that includes each employee's last name, employee identification number, date of hire, and salary. The report should include only those employees who have been with the company for more than one year and whose salary exceeds $40,000.
Which of the following SELECT statements will accomplish this task?
Respuesta
-
SELECT employee_id, last_name, salary
FROM employees
WHERE salary > 40000
AND hire_date =
(SELECT hire_date
FROM employees
WHERE (sysdate-hire_date) / 365 > 1);
-
SELECT employee_id, last_name, hire_date, salary
FROM employees
WHERE salary > 40000 AND hire_date =
(SELECT hire_date
FROM employees
WHERE (sysdate-hire_date) / 365 > 1);
-
SELECT employee_id, last_name, hire_date, salary
FROM employees
WHERE salary > 40000
AND (sysdate-hire_date) / 365 > 1;
-
SELECT employee_id, last_name, salary
FROM employees
WHERE salary > 40000
AND hire_date IN (sysdate-hire_date) / 365 > 1);
Pregunta 16
Pregunta
Which statement about group functions is true?
Respuesta
-
Group functions ignore null values.
-
Group functions can only be used in a SELECT list.
-
Group functions can be used in a WHERE clause.
-
A query that includes a group function in the SELECT list must include a GROUP BY clause.
Pregunta 17
Pregunta
You want to write a report that returns the average salary of all employees in the company, sorted by departments.
The EMPLOYEES table contains the following columns:
EMPLOYEES:
EMP_ID NUMBER(10) PRIMARY KEY
LNAME VARCHAR2(20)
FNAME VARCHAR2(20)
DEPT VARCHAR2(20)
HIRE_DATE DATE
SALARY NUMBER(10)
Which SELECT statement will return the information that you require?
Respuesta
-
SELECT salary(AVG), dept
FROM employees
GROUP BY dept;
-
SELECT dept, AVG(salary)
FROM employees
GROUP BY dept;
-
SELECT AVG (salary)
FROM employees
BY dept;
-
SELECT AVG salary
FROM employees
BY dept;
Pregunta 18
Pregunta
Evaluate this SELECT statement:
SELECT COUNT(employee_id), department_id
FROM employees
GROUP BY department_id;
You only want to include employees who earn more than 15000.
Which clause should you include in the SELECT statement?
Pregunta 19
Pregunta
What is the best explanation as to why this SQL statement will NOT execute?
SELECT department_id "Department", AVG (salary)"Average"
FROM employees
GROUP BY Department;
Respuesta
-
Salaries cannot be averaged as not all the numbers will divide evenly.
-
You cannot use a column alias in the GROUP BY clause.
-
The GROUP BY clause must have something to GROUP.
-
The department id is not listed in the departments table.
Pregunta 20
Pregunta
Which comparison operator can only be used with a single-row subquery?
Pregunta 21
Pregunta
Which statement about the <> operator is true?
Respuesta
-
The <> operator is NOT a valid SQL operator.
-
The <> operator CANNOT be used in a single-row subquery.
-
The <> operator returns the same result as the ANY operator in a subquery.
-
The <> operator can be used when a single-row subquery returns only one row.
Pregunta 22
Pregunta
The EMPLOYEES and ORDERS tables contain these columns:
EMPLOYEES
EMPLOYEE_ID NUMBER(10) NOT NULL PRIMARY KEY
FIRST_NAME VARCHAR2(30)
LAST_NAME VARCHAR2(30)
ADDRESS VARCHAR2(25)
CITY VARCHAR2(20)
STATE VARCHAR2(2)
ZIP NUMBER(9)
TELEPHONE NUMBER(10)
ORDERS
ORDER_ID NUMBER(10) NOT NULL PRIMARY KEY
EMPLOYEE_ID NUMBER(10) NOT NULL FOREIGN KEY
ORDER_DATE DATE
TOTAL NUMBER(10)
Which SELECT statement will return all orders generated by a sales representative named Franklin during the year 2001?
Respuesta
-
SELECT order_id, total
FROM ORDERS (SELECT employee_id
FROM employees
WHERE last_name = 'Franklin')
WHERE order_date BETWEEN '01-jan-2001' AND '31-dec-2001';
-
SELECT (SELECT employee_id FROM employees WHERE last_name = 'Franklin') AND order_id, total
FROM ORDERS
WHERE order_date BETWEEN '01-jan-2001' AND '31-dec-2001';
-
SELECT order_id, employee_id, total
FROM ORDERS
WHERE order_date BETWEEN '01-jan-2001' AND '31-dec-2001' AND emp_id = 'Franklin';
-
SELECT order_id, total
FROM ORDERS
WHERE employee_id = (SELECT employee_id FROM employees WHERE last_name = 'Franklin')
AND order_date BETWEEN '01-jan-2001' AND '31-dec-2001';
Pregunta 23
Pregunta
Which of the following is TRUE regarding the order of subquery execution?
Respuesta
-
The outer query is executed first.
-
The subquery executes once after the main query.
-
The subquery executes once before the main query.
-
The result of the main query is used with the subquery.
Pregunta 24
Pregunta
The TEACHERS and CLASS_ASSIGNMENTS tables contain these columns:
TEACHERS
TEACHER_ID NUMBER(5) Primary Key
NAME VARCHAR2 (25)
SUBJECT_ID NUMBER(5)
CLASS_ID NUMBER(5)
CLASS_ASSIGNMENTS
CLASS_ID NUMBER (5) Primary Key
TEACHER_ID NUMBER (5)
DATE
MAX_CAPACITY NUMBER (3)
All MAX_CAPACITY values are greater than 10. Which two SQL statements correctly use subqueries? (Choose two.)
(Choose all correct answers)
Respuesta
-
SELECT *
FROM class_assignments
WHERE max_capacity = (SELECT AVG(max_capacity) FROM class_assignments);
-
SELECT *
FROM teachers
WHERE teacher_id = (SELECT teacher_id FROM class_assignments WHERE class_id = 45963);
-
SELECT *
FROM teachers
WHERE teacher_id = (SELECT teacher_id, class_assignments WHERE max_capacity > 0);
-
SELECT *
FROM teachers
WHERE teacher_id LIKE (SELECT teacher_id FROM class_assignments WHERE max_capacity > 1000);
-
SELECT *
FROM class_assignments
max_capacity = (SELECT AVG(max_capacity) FROM class_assignments GROUP BY teacher_id);
Pregunta 25
Pregunta
You need to create a report to display the names of products with a cost value greater than the average cost of all products. Which SELECT statement should you use?
Respuesta
-
SELECT product_name
FROM products
WHERE cost > (SELECT AVG(cost)
FROM products);
-
SELECT product_name
FROM products
WHERE cost > AVG(cost);
-
SELECT AVG(cost), product_name
FROM products
WHERE cost > AVG(cost)
GROUP by product_name;
-
SELECT product_name
FROM (SELECT AVG(cost) FROM product)
WHERE cost > AVG(cost);
Pregunta 26
Pregunta
You need to display all the players whose salaries are greater than or equal to John Brown's salary. Which comparison operator should you use?
Pregunta 27
Pregunta
Using a subquery in which clause will return a syntax error?
Pregunta 28
Pregunta
Which statement about subqueries is true?
Respuesta
-
Subqueries should be enclosed in double quotation marks.
-
Subqueries cannot contain group functions.
-
Subqueries are often used in a WHERE clause to return values for an unknown conditional value.
-
Subqueries generally execute last, after the main or outer query executes.
Pregunta 29
Pregunta
If you use the equality operator (=) with a subquery, how many values can the subquery return?
Respuesta
-
ONLY 1
-
Up to 2
-
Up to 5
-
Unlimited
Pregunta 30
Pregunta
Which statement is false?
Respuesta
-
The WITH clause retrieves the results of one or more query blocks.
-
The WITH clause decreases performance.
-
The WITH clause makes the query simple to read.
-
The WITH clause stores the results for the user who runs the query.
Pregunta 31
Pregunta
Which answer is INCORRECT? The parent statement of a correlated subquery can be:
Respuesta
-
A SELECT statement
-
An INSERT statement
-
An UPDATE statement
-
A DELETE statement
Pregunta 32
Pregunta
The Oracle server performs a correlated subquery when the subquery references a column from a table referred to in the parent. True or False?
Pregunta 33
Pregunta
The WITH clause enables a SELECT statement to define the subquery block at the start of the query, process the block just once, label the results, and then refer to the results multiple times. True or False?
Pregunta 34
Pregunta
You need to create a SELECT statement that contains a multiple-row subquery. Which comparison operator(s) can you use?
Respuesta
-
IN, ANY, and ALL
-
LIKE
-
BETWEEN ... AND ...
-
=, <, and >
Pregunta 35
Pregunta
Examine the data in the PAYMENT table:
This statement fails when executed:
FROM payment
WHERE payment_id =
(SELECT payment_id
FROM payment
WHERE payment_date >= '05-JAN-2002' OR payment_amount > 500.00);
Which change could correct the problem?
Respuesta
-
Remove the subquery WHERE clause.
-
Change the outer query WHERE clause to 'WHERE payment_id IN'.
-
Include the PAYMENT_ID column in the select list of the outer query.
-
Remove the single quotes around the date value in the inner query WHERE clause.
Pregunta 36
Pregunta
Evaluate this SELECT statement:
SELECT player_id, name
FROM players
WHERE team_id IN
(SELECT team_id
FROM teams
WHERE team_id > 300 AND salary_cap > 400000);
What would happen if the inner query returned a NULL value?
Respuesta
-
No rows would be returned by the outer query.
-
A syntax error in the outer query would be returned.
-
A syntax error in the inner query would be returned.
-
All the rows in the PLAYER table would be returned by the outer query.
Pregunta 37
Pregunta
Assume all the column names are correct. The following SQL statement will execute which of the following?
INSERT INTO departments
(department_id, department_name, manager_id, location_id)
VALUES (70, 'Public Relations', 100, 1700);
Respuesta
-
100 will be inserted into the department_id column.
-
1700 will be inserted into the manager_id column.
-
70 will be inserted into the department_id column.
-
"Public Relations" will be inserted into the manager_name column.
Pregunta 38
Pregunta
The PRODUCTS table contains these columns:
PRODUCT_ID NUMBER NOT NULL
PRODUCT_NAME VARCHAR2 (25)
SUPPLIER_ID NUMBER NOT NULL
LIST_PRICE NUMBER (7,2)
COST NUMBER (5,2)
QTY_IN_STOCK NUMBER(4)
LAST_ORDER_DT DATE DEFAULT SYSDATE NOT NUL
Which INSERT statement will execute successfully?
Respuesta
-
INSERT INTO products (product_id, product_name, supplier_id, list_price, cost, qty_in_stock)
VALUES(2958, 'Cable', 8690, 7.09, 4.04, 700)
-
INSERT INTO products
VALUES (2958, 'Cable', 8690, 7.09, 4.04, SYSDATE);
-
INSERT INTO products(product_id, product_name)
VALUES (2958, 'Cable');
-
INSERT INTO products(product_id, product_name, supplier_id
VALUES (2958, 'Cable', 8690, SYSDATE);
Pregunta 39
Pregunta
The STUDENTS table contains these columns:
STU_ID NUMBER(9) NOT NULL
LAST_NAME VARCHAR2 (30) NOT NULL
FIRST_NAME VARCHAR2 (25) NOT NULL
DOB DATE
STU_TYPE_ID VARCHAR2(1) NOT NULL
ENROLL_DATE DATE
You create another table, named FT_STUDENTS, with an identical structure.You want to insert all full-time students who have a STU_TYPE_ID value of "F" into the new table. You execute this INSERT statement:
INSERT INTO ft_students
(SELECT stu_id, last_name, first_name, dob, stu_type_id, enroll_date
FROM students
WHERE UPPER(stu_type_id) = 'F');
What is the result of executing this INSERT statement?
Respuesta
-
All full-time students are inserted into the FT_STUDENTS table.
-
An error occurs because the FT_STUDENTS table already exists.
-
An error occurs because you CANNOT use a subquery in an INSERT statement.
-
An error occurs because the INSERT statement does NOT contain a VALUES clause.
Pregunta 40
Pregunta
You have been instructed to add a new customer to the CUSTOMERS table. Because the new customer has not had a credit check, you should not add an amount to the CREDIT column.
The CUSTOMERS table contains these columns:
CUST_ID NUMBER(10)
COMPANY VARCHAR2(30)
CREDIT NUMBER(10)
POC VARCHAR2(30)
LOCATION VARCHAR2(30)
Which two INSERT statements will accomplish your objective?
(Choose all correct answers)
Respuesta
-
INSERT INTO customers (cust_id, company, poc, location)
VALUES (200, 'InterCargo', 'tflanders', 'samerica');
-
INSERT INTO customers
VALUES (200, 'InterCargo', null, 'tflanders', 'samerica');
-
INSERT INTO customers
VALUES (cust_id, company, credit, poc, location) (200, 'InterCargo', 0, 'tflanders', 'samerica');
-
INSERT INTO customers
VALUES (200, InterCargo, 0, tflanders, samerica);
Pregunta 41
Pregunta
Which two commands can be used to modify existing data in a database row?
(Choose all correct answers)
Respuesta
-
DELETE
-
MERGE
-
SELECT
-
UPDATE
Pregunta 42
Pregunta
You need to delete a record in the EMPLOYEES table for Tim Jones, whose unique employee identification number is 348. The EMPLOYEES table contains these columns:
EMPLOYEE_ID NUMBER(5) PRIMARY KEY
LAST_NAME VARCHAR2(20)
FIRST_NAME VARCHAR2(20)
ADDRESS VARCHAR2(30)
PHONE NUMBER(10)
Which DELETE statement will delete the appropriate record without deleting any additional records?
Respuesta
-
DELETE FROM employees
WHERE employee_id = 348;
-
DELETE FROM employees
WHERE last_name = jones;
-
DELETE *
FROM employees
WHERE employee_id = 348;
-
DELETE 'jones'
FROM employees;
Pregunta 43
Pregunta
Which of the following represents the correct syntax for an INSERT statement?
Respuesta
-
INSERT VALUES INTO customers (3178 J. Smith 123 Main Street Nashville TN 37777;
-
INSERT INTO customers VALUES '3178' 'J.' 'Smith' '123 Main Street' 'Nashville' 'TN' '37777';
-
INSERT INTO customers VALUES ('3178', 'J.', 'Smith', '123 Main Street', 'Nashville', 'TN', '37777');
-
INSERT customers VALUES 3178, J., Smith, 123 Main Street, Nashville, TN, 37777;
Pregunta 44
Pregunta
What keyword in an UPDATE statement specifies the column that you want to change?
Pregunta 45
Pregunta
You need to update both the DEPARTMENT_ID and LOCATION_ID columns in the EMPLOYEES table using one UPDATE statement. Which clause should you include in the UPDATE statement to update multiple columns?
Respuesta
-
The USING clause
-
The ON clause
-
The WHERE clause
-
The SET clause
Pregunta 46
Pregunta
The EMPLOYEES table contains the following columns:
EMPLOYEE_ID NUMBER(10) PRIMARY KEY
LAST_NAME VARCHAR2(20)
FAST_NAME VARCHAR2(20)
DEPARTMENT_ID VARCHAR2(20)
HIRE_DATE DATE
SALARY NUMBER(9,2)
BONUS NUMBER(9,2)
You want to execute one DML statement to change the salary of all employees in department 10 to equal the new salary of employee number 89898. Currently, all employees in department 10 have the same salary value. Which statement should you execute?
Respuesta
-
UPDATE employees
SET salary = SELECT salary FROM employees WHERE employee_id = 89898;
-
UPDATE employees
SET salary = (SELECT salary FROM employees WHERE employee_id = 89898);
-
UPDATE employees
SET salary = (SELECT salary FROM employees WHERE employee_id = 89898)
WHERE department_id = 10;
-
UPDATE employees
SET salary = (SELECT salary FROM employees WHERE employee_id = 89898 AND department_id = 10);
Pregunta 47
Pregunta
When the WHERE clause is missing in a DELETE statement, what is the result?
Respuesta
-
All rows are deleted from the table.
-
The table is removed from the database.
-
An error message is displayed indicating incorrect syntax.
-
Nothing. The statement will not execute.
Pregunta 48
Pregunta
What would happen if you issued a DELETE statement without a WHERE clause?
Respuesta
-
All the rows in the table would be deleted.
-
An error message would be returned.
-
No rows would be deleted.
-
Only one row would be deleted.
Pregunta 49
Pregunta
A column in a table can be given a default value. This option prevents NULL values from automatically being assigned to the column if a row is inserted without a specified value for the column. True or False?
Pregunta 50
Pregunta
Multi-table inserts can be conditional or unconditional. True or False?