Junetheriver/OpsEval huggingface dataset:
Question: Which is true about the & and && prefixes with substitution variables?
A.  Both & and && can prefix a substitution variable name in queries and DML statements.
B.  The && prefix will not prompt for a value even if the substitution variable is not previously 
defined in the session.
C.  An && prefix to an undefined substitution variable, which is referenced multiple times in 
multiple queries, will prompt for a value once per query.
D.  & can prefix a substitution variable name only in queries.
E.  An & prefix to an undefined substitution variable, which is referenced twice in the same query, 
will prompt for a value twicE.
Answer: A,E
Question: 13、A schema owner truncated a table in error and must recover the data
Which Oracle Flashback feature could be used to recover the data?
A. FLASHBACK VERSION QUERY
B.  FLASHBACK TABLE
C. FLASHBACK TRANSACTION
D.  FLASHBACK DATABASE
E.  FLASHBACK DATA ARCHIVE
Answer: D
Question: You have been tasked to create a table for a banking application.
One of the columns must meet three requirements:
1) Be stored in a format supporting date arithmetic without using conversion functions
2) Store a loan period of up to 10 years
3) Be used for calculating interest for the number of days the loan remains unpaid
Which data type should you use?
A.  TIMESTAMP WITH TIMEZONE
B.  TIMESTAMP
C.  TIMESTAMP WITH LOCAL TIMEZONE
D.  INTERVAL YEAR TO MONTH
E.  INTERVAL DAY TO SECOND
Answer: E
Question: "1. Which of the following is not a shutdown mode for Oracle database?
A. Shutdown immediate
B. Shutdown abort
C. Shutdown transactional
D. Shutdown poweroff"
Answer: D
Question: "80. Which of the following files is not necessary when the Oracle server starts up?
A. Data files
B. Control files
C. Log files
D. Archived log files"
Answer: D
Question: "10. Which of the following statements about parameter files and parameters is correct?
A. The content of dynamic parameter files (SPFILE) and static parameter files (PFILE) is the same, but they are saved in different formats.
B. Dynamic parameter files (SPFILE) only store dynamic parameters, while static parameter files (PFILE) only store static parameters.
C. Dynamic parameter files (SPFILE) can only be created through static parameter files (PFILE).
D. Static parameter files (PFILE) can only be created through dynamic parameter files (SPFILE)."
Answer: A
Question: The STORES table has a column START_DATE of data type DATE, containing the date the row was 
inserteD.
You only want to display details of rows where START_DATE is within the last 25 months.
Which WHERE clause can be used?
A.  WHERE MONTHS_BETWEEN (SYSDATE, start_datE.  <= 25
B.  WHERE ADD_MONTHS (start_date, 25) <= SYSDATE
C.  WHERE TO_NUMBER(start_date - SYSDATE.  <= 25
D.  WHERE MONTHS_BETWEEN(start_date, SYSDATE.  <= 25
Answer: A
Question: "179. View the structure of the PROMOTIONS table below: name Null Type
PROMO_ID NOT NULL NUMBER(6)
PROMO_NAME NOT NULL VARCHAR2(30)
PROMO_CATEGORY NOT NULL VARCHAR2(30)
PROMO_COST NOT NULL NUMBER(10,2)
Management wants to see the unique promotion costs for each promotion category. Which query below will get the desired result?
A. SELECT DISTINCT promo_cost, promo_category FROM promotions;
B. SELECT promo_category, DISTINCT promo_cost FROM promotions;
C. SELECT DISTINCT promo_cost, DISTINCT promo_category FROM promotions;
D. SELECT DISTINCT promo_category, promo_cost FROM promotions ORDER BY 1;"
Answer: D
Question: "26. In Oracle, which statement displays 0 when the COMM field is empty and displays the value of COMM when it is not empty?
A. SELECT ename, NVL(comm, 0) FROM emp;
B. SELECT ename, NULL(comm, 0) FROM emp;
C. SELECT ename, NULLIF(comm, 0) FROM emp;
D. SELECT ename, DECODE(comm, NULL, 0) FROM emp;"
Answer: A
Question: "To update the current row in a cursor result set, you should use the clause:
A. WHERE CURRENT OF
B. FOR UPDATE
C. FOR DELETE
D. FOR MODIFY"
Answer: A
Question: choose the best answer
Examine the desciption of the CUSTOMERS table:
Name Null? Type
-----------------------------------------------------------------------------------------
CUST_ID Not NULL VARCHAR2(6)
FIRST_NAME VARCHAR2(50)
LAST_NAME Not NULL VARCHAR2(50)
ADDRRESS VARCHAR2(50)
CITY VARCHAR2(25)
You want to display detalls of all castomers who reside in cities starting with the letter D followed 
by at least two character
Which query can be used?
A.  SELECT * FROM customers WHERE city = 'D_%';
B.  SELECT * FROM customers WHERE city = '%D_';
C.  SELECT * FROM customers WHERE city LIKE 'D_ _%';
D.  SELECT * FROM customers WHERE city LIKE 'D_';
Answer: C
Question: 102、Which operating system group is NOT needed to perform an Oracle Database installation?
A.  OSRACDBA
B.  OSDBA
C.  OSASM
D.  OSKMDBA
E ) OSOPER
Answer: E
Question: "59. Which of the following statements is correct for adding a primary key to the STUDENTS table?
A. ALTER TABLE students ADD PRIMARY KEY student_id
B. ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_iD.
C. ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id
D. ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_iD.
E. ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_iD."
Answer: D
Question: Examine the desaiption of the PRODUCT_INFORMATION table:
Name NULL? Type
------------------------------------------------------------------------
PROD_ID NOT NULL NUMBER(2)
PROD_NANE VARCRAR2 (10)
LIST_PRICE NUMBER(6,2)
Which query retrieves the number of products with a null list price?
A.  SELECT (COUNT(list_pricE.  FERM Product_intormation WHERE list_price=NULL;
B.  SELECT Count(nvl( list_price,0) )FROM pruduct_information WHERE list_price is null;
C.  SELECT COUNT(DISTINCT last_pricE.  FROM produet_infomation WHERE last_price is nulll.
D.  BELECT COUNT(list_pricE.  from proceduct_information where list_price is NULL;
Answer: B
Question: Examine the data in the NEW_EMPLOYEES table:
EMPLOYEE_ID NAME DEPARTMENT_ID MANAGER_ID JOB_ID SALARY
--------------------------------------------------------------------------------------------------------------------------------
101 David 20 120 SA_REP 14000
102 Sam 10 105 CLERK 12500
103 Andrew 20 120 FIN_ADMIN 14200
104 Adrian 30 108 MAR_CLERK 12500
105 Maria 30 108 FIN_ADMIN 15000
106 Tracy 40 110 AD_ASST 13000
108 Kate 30 110 FIN_DIR 16500
110 Anne 40 120 EX_DIR 18000
120 Fran 20 110 SQ_DIR 16500
Examine the data in the EMPLOYEES table:
EMPLOYEE_ID NAME JOB_ID SALARY
-----------------------------------------------------------------------------
101 David CLERK 14000
102 Sam SA_REP 11500
104 Adrian MAR_CLERK 12500
108 Kate FIN_DIR 16500
110 Annie EX_DIR 18000
You want to:
1. Update existing employee details in the EMPLOYEES table with data from the NEW_EMPLOYEES 
tablE.
2. Add new employee details from the NEW_EMPLOYEES table to the EMPLOYEES tablE.
Which statement will do this?
A.  MERGE INTO employees e
 USING new_employees ne
 ON (E.employee_id= nE.employee_iD. 
 WHEN FOUND THEN UPDATE SET E.name=nE.name, E.job_id= nE.job_id, E.salary= nE.salary
 WHEN NOT FOUND THEN INSERT VALUES (nE.employee_id, ne .name, nE.job_id, nE.salary);
B.  MERGE INTO employees e
 USING new_employees ne
 WHERE E.employee_id= nE.employee_id
 WHEN FOUND THEN UPDATE SET E.name= nE.name, E.job_id= nE.job_id, E.salaly= nE.salary
 WHEN NOT FOUND THEN INSERT VALUES (nE.employee_id, nE.name, nE.job_id, nE.salary) ;
C.  MERGE INTO employees e
 USING new_employees ne
 WHERE E.employee_id= nE.employee_id
 WHEN MATCHED THEN UPDATE SET E.name= nE.name, E.job_id= nE.job_id, E.salary= nE.salary
 WHEN NOT MATCHED THEN INSERT VALUES (nE.employee id, nE.name, nE.job_id, nE.salary) :
D.  MERGE INTO employees e
 USING new_employees ne
 ON (E.employee_id= ne .employee_iD. 
 WHEN MATCHED THEN UPDATE SET E.name=nE.name, E.job_id= nE.job_id, E.salary= nE.salary
 WHEN NOT MATCHED THEN INSERT VALUES (nE.employee_id, nE.name, nE.job_id, nE.salary);
Answer: D
Question: "100. Which of the following is not necessary for installing Oracle database server?
A. Installing operating system
B. Installing Oracle software
C. Creating database
D. Configuring DataGuard"
Answer: D
Question: "105. Which of the following memory areas does not belong to SGA?
A. PGA B. Log buffer C. Data buffer D. Shared pool"
Answer: A
Question: "54. Which of the following statements about the wildcard character "_" in partial match queries is correct?
A. "_" represents multiple characters.
B. "_" represents one character.
C. "_" cannot be used together with "%".
D. "_" represents zero or more characters."
Answer: B
Question: "60. To view the current value of sequence DEPT_DEPTNO, which pseudocolumn should be used?
A. CURRVAL
B. NEXTVAL
C. MAXVAL
D. MINVAL"
Answer: A
Question: "68. Which statement can directly call a procedure in SQL*Plus?
A. RETURN
B. CALL
C. SET
D. EXEC"
Answer: D
Question: "39. Which of the following statements about ROWNUM is correct?
A. ROWNUM is a column that actually exists in each table.
B. ROWNUM is a row number assigned to each row of data after each query is executed, starting from 0.
C. Any arithmetic operator can be used when ROWNUM is used as a conditional expression.
D. ROWNUM is often used for pagination queries."
Answer: D
Question: "158. In the relational model, the constraint of "not allowing duplicate tuples in a relation" is implemented through:
A. candidate keys B. primary keys C. foreign keys D. superkeys"
Answer: B
Question: "45. The structure of the STUDENT_GRADES table is as follows: STUDENT_ID NUMBER(12), SEMESTER_END DATE, GPA NUMBER(4,3). Display STUDENT_ID, SEMESTER_END, and GPA, sorted first by semester_end in ascending order, and then by GPA in descending order. 
A. SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester_end DESC, gpa DESC;
B. SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester_end ASC, gpa ASC;
C. SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester_end, gpa DESC;
D. SELECT student_id, semester_end, gpa FROM student_grades ORDER BY gpa DESC, semester_end DESC;
E. SELECT student_id, semester_end, gpa FROM student_grades ORDER BY gpa DESC, semester_end ASC;"
Answer: C
Question: "52. View ANN_SAL is based on the employee table, and the structure of the view is as follows: NAME NULL TYPE EMPNO NOT NULL NUMBER(4) YEARLY_SAL NUMBER(9,2) MONTHLY_SAL NUMBER(9,2). Which statement can retrieve data from the view ANN_SAL?
A. SELECT * FROM ANN_SAL
B. SELECT * FROM EMPLOYEE
C. SELECT * FROM VIEW ANN_SAL
D. SELECT * FROM VIEW ANN_SAL IS DON EMPLOYEE"
Answer: A
Question: "97. Analyze the following successfully executed statement:

CREATE TABLE rental (
rental_id int unsigned NOT NULL AUTO_INCREMENT,
rental_date datetime NOT NULL,
inventory_id int unsigned NOT NULL,
customer_id int unsigned NOT NULL,
return_date datetime DEFAULT NULL,
staff_id int unsigned NOT NULL,
last_update timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (rental_id)
ENGINE=InnoDB;

Now, consider the following query:

SELECT rental_id, customer_id
FROM rental
WHERE rental_date BETWEEN NOW() - INTERVAL 1 MONTH AND NOW()
AND inventory_id=42
AND staff_id=1024;

You want to add one or more indexes to minimize the workload of the query. Which of the following statements can accomplish this task?

A. ALTER TABLE rental
ADD INDEX (inventory_id),
ADD INDEX (staff_id),
ADD INDEX (rental_date),
ADD INDEX (customer_id);

B. ALTER TABLE rental
ADD INDEX (inventory_id, staff_id, rental_date, customer_id);

C. ALTER TABLE rental
ADD INDEX (inventory_id, staff_id, customer_id, rental_id, rental_date);

D. ALTER TABLE rental
ADD INDEX (inventory_id),
ADD INDEX (staff_id),
ADD INDEX (rental_date);

E. ALTER TABLE rental
ADD INDEX (rental_date, inventory_id, staff_id, customer_id);

F. ALTER TABLE rental
ADD INDEX (inventory_id, staff_id, rental_date); "
Answer: B
Question: Examine this query:
SELECT SUBSTR (SYSDATE, 1,5) "Result" FROM DUAL;
Which statement is true?
A.  It fails unless the expression is modified to TO_CHAR (SUBSTR (SYSDATE, 1, 5)).
B.  It fails unless the expression is modified to SUBSTR (TO_CHAR (SYSDATE. , 1, 5).
C.  It fails unless the expression is modified to SUBSTR (TO_CHAR (TRUNC (SYSDATE. ), 1, 5).
D.  It executes successfully with an implicit data type conversion.
Answer: D
Question: "101. Which one should be the expected state of a Data Guard standby database?
A. Open & READ ONLY WITH APPLYING
B. Mounted & READ ONLY WITH APPLYING
C. Mounted & READ ONLY
D. Open & READ ONLY"
Answer: A
Question: 10、A user complains about poor database performance
You want to verify if the user's session has waited for certain types of I/O activity
Which view displays all waits waited on by a session at least once?
A.  V$SESSTAT
B.  V$SESSION WAIT
C.  V$SESSION EVENT
D.  V$SESSION
E.  V$SESSION WAIT CLASS
Answer: C
Question: "16. Connect to a certain PDB database (ERP1) using sys and issue the following authorization command: Grant create session to abc container=all; Which of the following statements is correct?
A. This authorization will result in an error.
B. This authorization only takes effect within ERP1.
C. This authorization only takes effect within the root container CDB$ROOT.
D. This authorization takes effect in both ERP1 and CDB$ROOT."
Answer: A
Question: Examine this statement:
SELECT 1 AS id, 'John' AS first_name
 FROM dual
UNION
SELECT 1, 'John' AS name
 FROM dual
ORDER BY 1;
What is returned upon execution?
A.  0 rows
B.  2 rows
C.  1 row
D.  an error
Answer: C
Question: You execute this query: 
SELECT TO_CHAR (NEXT_DAY (LAST_DAY (SYSDATE. , 'MON') , 'dd "Monday for" fmMonth rrrr' )
 FROM DUAL;
What is the result?
A.  It executes successfully but does not return any result.
B.  It generates an error.
C.  It returns the date for the first Monday of the next month.
D.  It returns the date for the last Monday of the current month.
Answer: C
Question: "145. What information will be displayed when querying the data dictionary DBA_USERS?
A. The tablespace quota for all users.
B. The tablespace quota for the current user.
C. The creation date of the database user.
D. Whether the current user has unlimited quota on a tablespace."
Answer: A
Question: "111. Locks are used to provide ________.
A. improved performance
B. data integrity and consistency
C. availability and ease of maintenance
D. user security"
Answer: B
Question: "164. The correct description of a database is: 
A. A database is a DBF file 
B. A database is a relationship 
C. A database is a structured collection of data 
D. A database is a set of files"
Answer: C
Question: "107. When creating a user in Oracle, if the DEFAULT TABLESPACE keyword is not mentioned, Oracle will allocate a tablespace to the user as the default tablespace.
A. HR
B. SCOTT
C. SYSTEM
D. SYS"
Answer: C
Question: 6. What does DBWR do when the COMMIT command is issued?
A. It immediately writes the log buffer to disk.
B. It immediately writes the data buffer to disk.
C. It notifies LGWR to write the log.
D. It does nothing.
Answer: D
Question: "162. SQL language is a language for ________. 
A. hierarchical databases 
B. network databases 
C. relational databases 
D. databases"
Answer: C
Question: "4. Which of the following is not a state of the online log group?
A. UNUSED
B. NOACTIVE
C. INACTIVE
D. ACTIVEE.CURRENT"
Answer: B
Question: "171. In table emp, calculate the annual salary of employees as SAL*12 and generate an alias as Annual Salary.
A. SELECT ename, sal*12, Annual Salary FROM emp;
B. SELECT ename, sal*12 "Annual Salary" FROM emp;
C. SELECT ename, sal*12 AS Annual Salary FROM emp;
D. SELECT ename, sql*12 AS INICTAP("Annual Salary") FROM emp;"
Answer: B
Question: Examine this query:
SELECT TRUNC (ROUND(156.00,-2),-1) FROM DUAL;
What is the result?
A.  16
B.  160
C.  150
D.  200
E.  100
Answer: D
Question: "73. In ORACLE, the operator used to determine if a column value is null is:
A. ==NULL
B. NULLIS
C. AS NULL
D. IS NULL"
Answer: C
Question: "42. Which command can ensure that only the data of table employeE. is deleted while keeping the structure of the table and it is necessary to be able to roll back?
A. DROP TABLE employeE.
B. DELETE FROM employeE.
C. TRUNCATE TABLE employeE.
D. This task can't be accomplished."
Answer: B
Question: "44. The table structure of EMP is as follows: ENAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATE Which sentence lists employees who have worked for more than five years in the company?
A. SELECT ENAME FROM EMP WHERE SYSDATE-HIRE_DATE > 5;
B. SELECT ENAME FROM EMP WHERE HIRE_DATE-SYSDATE > 5;
C. SELECT ENAME FROM EMP WHERE (SYSDATE-HIRE_DATE) /365 > 5;
D. SELECT ENAME FROM EMP WHERE (SYSDATE-HIRE_DATE) * 365 > 5;"
Answer: C
Question: "51. Regarding the granting of permissions, which of the following statements is correct?
A. The WITH GRANT OPTION option can achieve the transfer of system permissions.
B. The WITH ADMIN OPTION option can achieve the transfer of object permissions.
C. Both of the above statements are correct.
D. Neither of the above statements is correct."
Answer: D
Question: "57. Which of the following statements about null values is correct?
A. Any arithmetic expression that contains a null value results in a null value.
B. The concatenation of a string that contains a null value with an empty string results in a null value.
C. The syntax for using null values as a condition is to write: field = null.
D. If the table Emp has 5 records with empID values of 1, 2, 3, 4, and 5, then the query Select * from Emp where empID not in (2, 3, 4, null) will result in 2 records."
Answer: A
Question: "64. In Oracle database, user schema stores data dictionary tables and view objects.
A. SYS
B. SYSTEM
C. SCOTT
D. SYSDBA"
Answer: A
Question: "131. The database operated in non-archival logging mode has been disabled.
A. Archival logging
B. Online logging
C. Log writing program
D. Log file"
Answer: A
Question: "188. Which statement is correct regarding backup based on user management?
A. It is not necessary to close the database, direct low-level copying can ensure consistency.
B. The database can be cleanly and consistently closed, and then low-level copying can ensure consistency.
C. It is not necessary to close the database because the underlying files are unrelated to the Oracle system.
D. It is not necessary to close the database, but the backup tablespace needs to be set to backup mode."
Answer: B,D
Question: "34. Which activity will result in an automatic rollback?
A. GRANT
B. CREATE
C. System crash
D. Exiting from SQL*Plus"
Answer: C
Question: The CUSTOMERS table has a CUST_LAST_NAME column of data type VARCHAR2.
The table has two rows whose COST_LAST_MANE values are Anderson and Ausson. 
Which query produces output for CUST_LAST_SAME containing Order for the first 
row and Aus for the second?
A.  SELECT REPLACE (REPLACE(cust_last_name,'son',''),'An','O') FROM customers;
B.  SELECT REPLACE (TRIM(TRALING 'son' FROM cust_last_namE. , 'An','O') FROM 
customers;
C.  SELECT INITCAP (REPLACE(TRIM('son' FROM cust_last_namE. ,'An','O')) FROM 
customers;
D.  SELECT REPLACE (SUBSTR(cust_last_name,-3), 'An', 'O') FROM customers;
Answer: A
Question: "33. The query statement SELECT SUBSTR('Hello World',4,5) FROM DUAL; returns a result. Which one is correct?
A. loWor B. World C. lloWo D. lo Wo"
Answer: D
Question: "160. The command to delete a table from a database is:
A. DROP TABLE B. ALTER TABLE C. DELETE TABLE D. USE"
Answer: C
Question: 33、Which three are true about using Database Upgrade Assistant(DBUA. to upgrade a database?
A.  Multiple databases with the same ORACLE HOME can be upgraded simultaneously
B.  All pluggable databases are automatically upgraded as part of a container database upgradE.
C.  DBUA must be launched from the target Oracle Home
D.  The Pre-upgrade Information Tool script is executed by DBUA
E.  A whole database backup must exist before upgrade
F.  The database must be opened in read-only modE.
Answer: B,C,D
Question: The SALES table has columns PROD_ID and QUANTITY_SOLD of data type NUMBER.
Which two querdes execute successfully?
A.  SELECT COUNT(prod_iD.  FROM sales WHERE quantity_sold>55000 GROUP BY prod_id;
B.  SELECT prod_id FROM sales WHERE quantity_sold > 55000 GROUP BY prod_id HAVING 
COUNT(*) > 10;
C.  SELECT COUNT(prod_iD.  FROM sales GROUP BY prod_id WHERE quantity_sold > 55000;
D.  SELECT prod_id FROM sales WHERE quantity_sold> 55000 AND COUNT(*) > 10 GROUP BY 
COUNT(*) > 10;
E.  SELECT prod_id FROM sales WHERE quantity_sold> 55000 AND COUNT(*) > 10 GROUP BY 
prod_id HAVING COUNT(*) > 10;
Answer: A,B
Question: Which three statements are true about inner and outer joins?
A.  A full outer join returns matched and unmatched rows.
B.  Outer joins can only be used between two tables per query.
C.  Outer joins can be used when there are multiple join conditions on two tables.
D.  A left or right outer join returns only unmatched rows.
E.  A full outer join must use Oracle syntax.
F.  An inner join returns matched rows.
Answer: A,C,F
Question: Which three statements are true regarding single row subqueries?
A.  They can be used in the WHERE clausE.
B.  They must be placed on the right side of the comparison operator or condition.
C.  They must return a row to prevent errors in the SQL statement.
D.  They must be placed on the left side of the comparison operator or condition.
E.  A SQL statement may have multiple single row subquery blocks.
F.  They can be used in the HAVING clausE.
Answer: A,C,E
Question: Examine the description of the EMPLOYEES table:
Name Null? Type
-------------------------------------------------------------
EMPLOYEE_ID NOT NULL NUMBER(4)
EMPLOYEE_NAME NOT NULL VARCHAR2 (100)
SALARY NOT NULL NUMBER(6,2) .
DEPARTMENT_ID NOT NULL NUMBER(4)
Which statement will fail?
A.  SELECT department_id, COUNT(*)
FROM employees
WHERE department_id <> 90
HAVING COUNT(*) >= 3
GROUP BY department_id;
B.  SELECT department_id, COUNT (*)
FROM employees
WHERE department_id <> 90
AND COUNT(*) >= 3
GROUP BY department_id;
C.  SELECT department_id, COUNT (*)
FROM employees
WHERE department_id < 90
GROUP BY department_id
HAVING COUNT(*) >= 3;
D.  SELECT department_id, COUNT (*)
FROM employees
HAVING department_id < 90
AND COUNT(*) >= 3
GROUP BY department_id;
Answer: B
Question: "132. Which backup method requires the database to be completely shut down?
A. Database backup in non-archived log mode
B. Database backup in archived log mode
C. Logical backup using export utility
D. None of the above"
Answer: A
Question: Table ORDER_ITEMS contains columns ORDER_ID, UNIT_PRICE and QUANTITY, of data type 
NUMBER.
Examine these SQL statements:
Statement 1:
SELECT MAX (unit_price * quantity) "Maximum order"
FROM order_items;
Statement 2:
SELECT MAX (unit_price * quantity) "Maximum order"
FROM order_items
GROUP BY order_id;
Which two statements are true?
A.  Both statements will return NULL if either UNIT_PRICE or QUANTITY contains NULL.
B.  Statement 2 may return multiple rows of output.
C.  Statement 2 returns only one row of output.
D.  Statement 1 returns only one row of output.
E.  Both the statements give the same output.
Answer: B,D
Question: "62. In the logical structure of an Oracle database, the components are as follows: 1. Tablespace 2. Data block 3. Extent 4. Segment. The correct order of these components from largest to smallest is: A. 1→2→3→4 B. 1→4→3→2 C. 1→3→2→4 D. 4→1→3→2."
Answer: B
Question: 64、Which three are true about the Oracle Optimizer?
A.  It can re-optimize execution plans after previous executions detect suboptimal plans
B.  It considers the filters in WHERE clauses when generating execution plans for SQL statements
C.  It can only use SQL Plan Directives tied to the SQL statement for which a plan is being 
generated
D.  It considers object statistics when generating execution plans for SQL statements
E.  It updates stale object statistics in the Data Dictionary
F.  It obeys all hints.
Answer: A,B,D
Question: "13. How to close a specific PDB (e.g. ERP1) in the root container of Oracle 12c?
A. Alter pluggable database erp1 close immediate;
B. Shutdown immediate;
C. Alter pluggable database all close immediate;
D. Shutdown abort;"
Answer: A