What does the FORCE option for creatin...

单项选择题What does the FORCE option for creating a view do?（）

A.creates a view with constraints
B.creates a view even if the underlying parent table has constraints
C.creates a view in another schema even if you don't have privileges
D.creates a view regardless of whether or not the base tables exist

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1.多项选择题Which three SELECT statements display 2000 in the format "$2,000.00"? （）

A. SELECT TO_CHAR(2000, '$#,###.##') FROM dual;
B. SELECT TO_CHAR(2000, '$0,000.00') FROM dual;
C. SELECT TO_CHAR(2000, '$9,999.00') FROM dual;
D. SELECT TO_CHAR(2000, '$9,999.99') FROM dual;
E. SELECT TO_CHAR(2000, '$2,000.00') FROM dual;
F. SELECT TO_CHAR(2000, '$N,NNN.NN') FROM dual;

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2.单项选择题Which are iSQL*Plus commands? （）

A.INSERT
B.UPDATE
C.SELECT
D.DESCRIBE
E.DELETE
F.RENAME

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3.多项选择题 Examine the description of the MARKS table:
STD_ID NUMBER(4)
STUDENT_NAME VARCHAR2(30)
SUBJ1 NUMBER(3)
SUBJ2 NUMBER(3)
SUBJ3 NUMBER(3)
SUBJ1, SUBJ2, and SUBJ3 indicate the marks (grades) obtained by a student in the three subjects. Which two statements are valid? （）

A.SELECT SUM(subj1, subj2, subj3) FROM marks;
B.SELECT SUM(subj1 + subj2 + subj3) FROM marks;
C.SELECT SUM(subj1), SUM(subj2), SUM(subj3) FROM marks;
D.SELECT MAX(subj1, subj2, subj3) FROM marks;
E.SELECT MINIMUM(subj1) FROM marks;
F.SELECT COUNT(std_id) FROM marks WHERE subj1 >= AVG(subj1);

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4.单项选择题 Examine the description of the EMPLOYEES table:

Which statement produces the number of different departments that have employees with last name Smith?（）

A.SELECT COUNT(*) FROM employees WHERE last_name='Smith';
B.SELECT COUNT(dept_id) FROM employees WHERE last_name='Smith';
C.SELECT DISTINCT(COUNT(dept_id)) FROM employees WHERE last_name='Smith';
D.SELECT COUNT(DISTINCT dept_id) FROM employees WHERE last_name='Smith';
E.SELECT UNIQUE(dept_id) FROM employees WHERE last_name='Smith';

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5.单项选择题Which SELECT statement should you use to extract the year from the system date and display it in the format "1998"?（）

A.SELECT TO_CHAR(SYSDATE,'yyyy') FROM dual;
B.SELECT TO_DATE(SYSDATE,'yyyy') FROM dual;
C.SELECT DECODE(SUBSTR(SYSDATE, 8), 'YYYY') FROM dual;
D.SELECT DECODE(SUBSTR(SYSDATE, 8), 'year') FROM dual;
E.SELECT TO_CHAR(SUBSTR(SYSDATE, 8,2),'yyyy') FROM dual;

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6.单项选择题In which scenario would an index be most useful?（）

A.The indexed column is declared as NOT NULL.
B.The indexed columns are used in the FROM clause.
C.The indexed columns are part of an expression.
D.The indexed column contains a wide range of values.

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7.单项选择题 Evaluate these two SQL statements:
SELECT last_name, salary , hire_date
FROM EMPLOYEES
ORDER BY salary DESC;
SELECT last_name, salary , hire_date
FROM EMPLOYEESORDER BY 2 DESC;
What is true about them?（）

A.The two statements produce identical results.
B.The second statement returns a syntax error.
C.There is no need to specify DESC because the results are sorted in descending order by default.
D.The two statements can be made to produce identical results by adding a column alias for the salary column in the second SQL statement.

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8.单项选择题Which SQL statement accepts user input for the columns to be displayed, the table name, and the WHERE condition?（）

A.SELECT &1, "&2" FROM &3 WHERE last_name = '&4';
B.SELECT &1, '&2' FROM &3 WHERE '&last_name = '&4'';
C.SELECT &1, &2 FROM &3 WHERE last_name = '&4';
D.SELECT &1, '&2' FROM EMP WHERE last_name = '&4';

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9.多项选择题Click the Exhibit button and examine the data in the EMPLOYEES table. Which three subqueries work?（）

A.SELECT * FROM employees where salary > (SELECT MIN(salary) FROM employees GROUP BY department_id);
B.SELECT * FROM employees WHERE salary = (SELECT AVG(salary) FROM employees GROUP BY department_id);
C.SELECT distinct department_id FROM employees WHERE salary > ANY (SELECT AVG(salary) FROM employees GROUP BY department_id);
D.SELECT department_id FROM employees WHERE salary > ALL (SELECT AVG(salary) FROM employees GROUP BY department_id);
E.SELECT last_name FROM employees WHERE salary > ANY (SELECT MAX(salary) FROM employees GROUP BY department_id);
F.SELECT department_id FROM employees WHERE salary > ALL (SELECT AVG(salary) FROM employees GROUP BY AVG(SALARY));

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10.单项选择题Which SQL statement defines a FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）

A.CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);
B.CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
C.CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));
D.CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));

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