更多"The EMPLOYEES table has these colum"的相关试题:
[单项选择] The EMPLOYEES table has these columns: LAST NAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATE Management wants to add a default value to the SALARY column. You plan to alter the table by using this SQL statement: ALTER TABLE EMPLOYEES MODIFY ( SALARY DEFAULT 5000); What is true about your ALTER statement?（）
A. Column definitions cannot be altered to add DEFAULT values.
B. A change to the DEFAULT value affects only subsequent insertions to the table.
C. Column definitions cannot be altered at add DEFAULT values for columns with a NUMBER data type.
D. All the rows that have a NULL value for the SALARY column will be updated with the value 5000.
[单项选择]The EMPLOYEES table has these columns:LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATEManagement wants to add a default value to the SALARY column. You plan to alter the table by using this SQL statement:ALTER TABLE EMPLOYEES MODIFY (SALARY DEFAULT 5000);Which is true about your ALTER statement?（）
A. Column definitions cannot be altered to add DEFAULT values.
B. A change to the DEFAULT value affects only subsequent insertions to the table.
C. Column definitions cannot be altered to add DEFAULT values for columns with a NUMBER data type.
D. All the rows that have a NULL value for the SALARY column will be updated with the value 5000.
[单项选择] The EMPLOYEES table contains these columns: LAST_NAME VARCHAR2 (25) SALARY NUMBER (6,2) COMMISSION_PCT NUMBER (6) You need to write a query that will produce these results: 1.Display the salary multiplied by the commission_pct. 2.Exclude employees with a zero commission_pct. 3.Display a zero for employees with a null commission value. Evaluate the SQL statement: SELECT LAST_NAME, SALARY*COMMISSION_PCT FROM EMPLOYEES WHERE COMMISSION_PCT IS NOT NULL; What does the statement provide?（）
A. all of the desired results
B. two of the desired results
C. one of the desired results
D. an error statement
[单项选择] The EMPLOYEES table contains these columns: EMPLOYEE_ID NUMBER(4) ENAME VARCHAR2 (25) JOB_ID VARCHAR2(10) Which SQL statement will return the ENAME, length of the ENAME, and the numeric position of the letter "a" in the ENAME column, for those employees whose ENAME ends with a the letter "n"?（）
A. SELECT ENAME, LENGTH(ENAME), INSTR(ENAME, 'a') FROM EMPLOYEES WHERE SUBSTR (ENAME, -1,1) = 'n';
B. SELECT ENAME, LENGTH(ENAME), INSTR(ENAME, ,-1,1) FROM EMPLOYEES WHERE SUBSTR (ENAME, -1,1) = 'n';
C. SELECT ENAME, LENGTH(ENAME), SUBSTR(ENAME, -1,1) FROM EMPLOYEES WHERE INSTR (ENAME, 1,1) = 'n';
D. SELECT ENAME, LENGTH(ENAME), SUBSTR(ENAME, -1,1) FROM EMPLOYEES WHERE INSTR (ENAME, -1,1) = 'n';
[多项选择] Examine the data in the EMPLOYEES table: LAST_NAME DEPARTMENT_ID SALARY Getz 10 3000 Davis 20 1500 Bill 20 2200 Davis 30 5000 ... 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 ANG (SALARY));
[单项选择] The EMP table contains these columns: LAST_NAME VARCHAR2 (25) SALARY NUMBER (6,2) DEPARTMENT_ID NUMBER (6) You need to display the employees who have not been assigned to any department. You write the SELECT statement: SELECT LAST_NAME, SALARY, DEPARTMENT_ID FROM EMP WHERE DEPARTMENT_ID = NULL; What is true about this SQL statement ?（）
A. The SQL statement displays the desired results.
B. The column in the WHERE clause should be changed to display the desired results.
C. The operator in the WHERE clause should be changed to display the desired results.
D. The WHERE clause should be changed to use an outer join to display the desired results.
[单项选择] The EMPLOYEE tables has these columns: LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) COMMISSION_PCT NUMBER(5,2) You want to display the name and annual salary multiplied by the commission_pct for all employees. For records that have a NULL commission_pct, a zero must be displayed against the calculated column. Which SQL statement displays the desired results? （）
A. SELECT last_name, (salary * 12) * commission_pct FROM EMPLOYEES;
B. SELECT last_name, (salary * 12) * IFNULL(commission_pct, 0) FROM EMPLOYEES;
C. SELECT last_name, (salary * 12) * NVL2(commission_pct, 0) FROM EMPLOYEES;
D. SELECT last_name, (salary * 12) * NVL(commission_pct, 0) FROM EMPLOYEES;
[单项选择] Given table T1 has column I1 containing the following data: I1 1 2 3 4 If the following sequence of SQL statements is applied within a single unit of work: UPDATE t1 SET i1 = 3 WHERE i1 = 2; S AVEPOINT s1 ON ROLLBACK RETAIN CURSORS; UPDATE t1 SET i1 = 5 WHERE i1 = 3; SAVEPOINT s2 ON ROLLBACK RETAIN CURSORS;INSERT INTO t1 (i1) VALUES (6); ROLLBACK TO SAVEPOINT s1; UPDATE t1 SET i1 = 2 WHERE i1 = 4; COMMIT; What is the expected sequence of values returned from?（） SELECT i1 FROM t1 ORDER BY i1
A. 1, 2, 3, 3
B. 1, 2, 2, 4
C. 1, 2, 3, 3, 6
D. 1, 2, 2, 5, 6
