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在Oracle中,有一个名为seq的序列对象,假定此时查看seq序列当前值显示为7,那么执行下面的sql insert into stu(id, name) values(seq.NEXTVAL,’tom’ );很不幸,这个insert没有执行成功,随后马上执行rollback,问:此时查看seq序列当前值显示为()

  • A、 6
  • B、8
  • C、7
  • D、不能确定

参考答案

更多 “在Oracle中,有一个名为seq的序列对象,假定此时查看seq序列当前值显示为7,那么执行下面的sql insert into stu(id, name) values(seq.NEXTVAL,’tom’ );很不幸,这个insert没有执行成功,随后马上执行rollback,问:此时查看seq序列当前值显示为()A、 6B、8C、7D、不能确定” 相关考题
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考题 单选题Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) SAL NUMBER MGR_ID NUMBER DEPARTMENT_ID NUMBER You want to create a SQL script file that contains an INSERT statement. When the script is run, the INSERT statement should insert a row with the specified values into the EMPLOYEES table. The INSERT statement should pass values to the table columns as specified below: EMPLOYEE_ID: Next value from the sequence EMP_ID_SEQEMP_NAME and JOB_ID: As specified by the user during run time, through substitution variables SAL: 2000 MGR_ID: No value DEPARTMENT_ID: Supplied by the user during run time through substitution variable. The INSERT statement should fail if the user supplies a value other than 20 or 50. Which INSERT statement meets the above requirements?()A INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, ename','jobid', 2000, NULL, did);B INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, 'ename', 'jobid', 2000, NULL, did IN (20,50));C INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50)) VALUES (emp_id_seq.NEXTVAL, ename','jobid', 2000, NULL, did);D INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50) WITH CHECK OPTION) VALUES (emp_id_seq.NEXTVAL, ename','jobid', 2000, NULL, did);E INSERT INTO (SELECT * FROM employees WHERE (department_id = 20 AND department_id = 50) WITH CHECK OPTION ) VALUES (emp_id_seq.NEXTVAL, ename','jobid', 2000, NULL, did);

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