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单选题
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.


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更多 “单选题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.” 相关考题
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考题 单选题Examine the description of the EMPLOYEES table: EMP_ID NUMBER(4) NOT NULL LAST_ NAME VARCHAR2(30) NOT NULL FIRST_NAME VARCHAR2(30) DEPT_ID NUMBER(2) JOB_CAT VARCHAR2(30) SALARY NUMBER(8,2) Which statement shows the department ID, minimum salary, and maximum salary paid in that department, only if the minimum salary is less than 5000 and maximum salary is more than 15000?()A SELECT dept_id, MIN(salary), MAX(salary) FROM employees WHERE MIN(salary) 5000 AND MAX(salary) 15000;B SELECT dept_id, MIN(salary), MAX(salary) FROM employees WHERE MIN(salary) 5000 AND MAX(salary) 15000 GROUP BY dept_id;C SELECT dept_id, MIN(salary), MAX(salary) FROM employees HAVING MIN(salary) 5000 AND MAX(salary) 15000;D SELECT dept_id, MIN(salary), MAX(salary) FROM employees GROUP BY dept_id HAVING MIN(salary) 5000 AND MAX(salary) 15000;E SELECT dept_id, MIN(salary), MAX(salary) FROM employees GROUP BY dept_id, salary HAVING MIN(salary) 5000 AND MAX(salary) 15000;

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考题 单选题The EMP table has these columns: ENAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATE Management wants a list of names of employees who have been with the company for more than five years. Which SQL statement displays the required results? ()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;

考题 单选题The EMP table contains these columns: EMPLOYEE_ID NUMBER(4) EMPNAME VARCHAR2 (25) SALARY NUMBER(9,2) HIRE_DATE DATE You query the database with this SQL statement: SELECT empname,hire_date HIREDATE, salary FROM EMP ORDER BY hire_date; How will the results be sorted?()A randomlyB ascending by dateC descending by dateD ascending alphabeticallyE descending alphabetically

考题 单选题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 resultsB Two of the desired resultsC One of the desired resultsD An error statement

考题 单选题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.

考题 单选题The EMP table has these columns: ENAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATE Management wants a list of names of employees who have been with the company for more than five years. Which SQL statement displays the required results? ()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;

考题 单选题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 resultsB Two of the desired resultsC One of the desired resultsD An error statement

考题 单选题Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: LAST NAME VARCNAR2(35) NOT NULL SALARY NUMBER(9,2) NOT NULL COMMISION_PCT NUMBER(4,2) Which statement ensures that a value is displayed in the calculated columns for all employees? ()A SELECT last_name, 12*salary* commission_pct FROM emp;B SELECT last_name, 12*salary* (commission_pct,0) FROM emp;C SELECT last_name, 12*salary*(nvl(commission_pct,0)) FROM emp;D SELECT last_name, 12*salary*(decode(commission_pct,0)) FROM emp;