单选题The command echo $! will produce what output？（）Athe process id of last background commandBthe exit status of the last commandCthe exit status of the last background commandDthe process id of the current shellEthe name of the command being executed

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单选题

The command echo $! will produce what output？（）

the process id of last background command

the exit status of the last command

the exit status of the last background command

the process id of the current shell

the name of the command being executed

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第1题

单选题Click the Exhibit button and examine the data in the EMPLOYEES and DEPARTMENTS tables.You want to retrieve all employees, whether or not they have matching departments in the departments table. Which query would you use?（）A SELECT last_name, department_name FROM employees NATURAL JOIN departments;B SELECT last_name, department_name FROM employees JOIN departments ;C SELECT last_name, department_name FROM employees e JOIN departments d ON (e.department_id = d.department_id);D SELECT last_name, department_name FROM employees e RIGHT OUTER JOIN departments d ON (e.department_id = d.department_id);E SELECT last_name, department_name FROM employees FULL JOIN departments ON (e.department_id = d.department_id);F SELECT last_name, department_name FROM employees e LEFT OUTER JOIN departments d ON (e.department_id = d.department_id);

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第2题

单选题The command echo $! will produce what output？（）Athe process id of last background commandBthe exit status of the last commandCthe exit status of the last background commandDthe process id of the current shellEthe name of the command being executed

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第3题

单选题Examine the structure of the EMPLOYEES and DEPARTMENTS tables: EMPLOYEES EMPLOYEE_ID NUMBER DEPARTMENT_ID NUMBER MANAGER_ID NUMBER LAST_NAME VARCHAR2(25) DEPARTMENTS DEPARTMENT_ID NUMBER MANAGER_ID NUMBER DEPARTMENT_NAME VARCHAR2(35) LOCATION_ID NUMBER You want to create a report displaying employee last names, department names, and locations. Which query should you use?（）A SELECT e.last_name, d. department_name, d.location_id FROM employees e NATURAL JOIN departments D USING department_id ;B SELECT last_name, department_name, location_id FROM employees NATURAL JOIN departments WHERE e.department_id =d.department_id;C SELECT e.last_name, d.department_name, d.location_id FROM employees e NATURAL JOIN departments d;D SELECT e.last_name, d.department_name, d.location_id FROM employees e JOIN departments d USING (department_id );

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第4题

单选题The administrator wants to verify the current state of the OSPF database loading process. Which show command should the administrator use?（）A show ip ospf [process - id] interfaceB show ip ospf neighborC show ip ospf [process - id]D show ip ospf [process - id area - id] database

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第5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) 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 UNIQE (dept_id) FROM employees WHERE last _name='smith';

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第6题

单选题Which statement is true regarding the Archiver （ARCn） process，archived log files，and recovery？（）A A database backup, combined with archived redo log files, guarantees that all committed data can be recovered to the point of failure. B During recovery the ARCn background process copies its redo entries identified for recovery by the control file to the data files. C After each write to an archived log, the mandatory background process ARCn writes its log sequence number and the first and last SCN number within the log sequence to the control file. D At database recover time, and archived redo log is uniquely identified for recovery use by its redo thread number and destination ID number retrieved from the control file.

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第7题

单选题Examine the structure of the EMPLOYEES table: Column name Data type Remarks EMPLOYEE_ID NUMBER NOT NULL, Primary Key LAST_NAME VARCNAR2(30) FIRST_NAME VARCNAR2(30) JOB_ID NUMBER SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER You need to create an index called NAME_IDX on the first name and last name fields of the EMPLOYEES table. Which SQL statement would you use to perform this task? （）A CREATE INDEX NAME _IDX (first_name, last_name);B CREATE INDEX NAME _IDX (first_name, AND last_name)C CREATE INDEX NAME_IDX ON (First_name, last_name);D CREATE INDEX NAME_IDX ON employees (First_name, AND last_name);E CREATE INDEX NAME_IDX ON employees (First_name, last_name);F CREATE INDEX NAME_IDX FOR employees (First_name, last_name);

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单选题The command echo $! will produce what output？（）A the process id of last background commandB the exit status of the last commandC the exit status of the last background commandD the process id of the current shellE the name of the command being exe

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