Examine the data in the EMPLOYEES table.EMPLOYEESEMP_NAME DEPT_ID MGR_ID JOB_ID SALARYEMPLOYEE_ID101 Smith 20 120 SA_REP 4000102 Martin 10 105 CLERK 2500103 Chris 20 120 IT_ADMIN 4200104 John 30 108 HR_CLERK 2500105 Diana 30 108 IT_ADMIN 5000106 Smith 40 110 AD.ASST 3000108 Jennifer 30 110 HR_DIR 6500110 Bob 40 EK_DIR 8000120 Revi 20 110 SA_DIR 6500On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:DELETE employee_id, salary, job_idFROM employeesWHERE dept_id = 90;Why does the DELETE statement fail when you execute it?（）A. There is no row with dept_id 90 in the EMPLOYEES table.B. You cannot delete the JOB_ID column because it is a NOT NULL column.C. You cannot specify column names in the DELETE clause of the DELETE statement.D. You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.
Examine the data in the EMPLOYEES table.EMPLOYEESEMP_NAME DEPT_ID MGR_ID JOB_ID SALARYEMPLOYEE_ID101 Smith 20 120 SA_REP 4000102 Martin 10 105 CLERK 2500103 Chris 20 120 IT_ADMIN 4200104 John 30 108 HR_CLERK 2500105 Diana 30 108 IT_ADMIN 5000106 Smith 40 110 AD.ASST 3000108 Jennifer 30 110 HR_DIR 6500110 Bob 40 EK_DIR 8000120 Revi 20 110 SA_DIR 6500On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:DELETE employee_id, salary, job_idFROM employeesWHERE dept_id = 90;Why does the DELETE statement fail when you execute it?（）
A. There is no row with dept_id 90 in the EMPLOYEES table.
B. You cannot delete the JOB_ID column because it is a NOT NULL column.
C. You cannot specify column names in the DELETE clause of the DELETE statement.
D. You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.
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We will do our best to ( ) shipment to meet your requirements in time. A.expectB.expediteC.exerciseD.examine
Examine the data in the EMPLOYEES and EMP_HIST tables:EMPLOYEESNAME DEPT_ID MGR_ID JOB_ID SALARYEMPLOYEE_ID101 Smith 20 120 SA_REP 4000102 Martin 10 105 CLERK 2500103 Chris 20 120 IT_ADMIN 4200104 John 30 108 HR_CLERK 2500105 Diana 30 108 IT_ADMIN 5000106 Smith 40 110 AD_ASST 3000108 Jennifer 30 110 HR_DIR 6500110 Bob 40 EX_DIR 8000120 Ravi 20 110 SA_DIR 6500EMP HISTEMPLOYEE_ID NAME JOB_ID SALARY101 Smith SA_CLERK 2000103 Chris IT_CLERK 2200104 John HR_CLERK 2000106 Smith AD_ASST 3000108 Jennifer HR_MGR 4500The EMP_HIST table is updated at the end of every year. The employee ID, name, job ID, and salary of each existing employee are modified with the latest data. New employee details are added to the table.Which statement accomplishes this task?（）A. UPDATE emp_hist SET employee_id, name, job_id, salary = (SELECT employee_id, name, job_id, salary FROM employees) WHERE employee_id IN (SELECT employee_id FROM employees);B. MERGE INTO emp_hist eh USING employees e ON (eh.employee_id = e.employee_id) WHEN MATCHED THEN UPDATE SET eh.name = e.name, eh.job_id = e.job_id, eh.salary = e.salary WHEN NOT MATCHED THEN INSERT VALUES (e.employee id, e.name, job id, e.salary);C. MERGE INTO emp_hist eh USING employees e ON (eh.employee_id = e.employee_id) WHEN MATCHED THEN UPDATE emp hist SET eh.name = e.name, eh.job_id = e.job_id, eh.salary = e.salary WHEN NOT MATCHED THEN INSERT INTO emp_hist VALUES (e.employees_id, e.name, e.job_id, e.salary);D. MERGE INTO emp_hist eh USING employees e WHEN MATCHED THEN UPDATE emp_hist SET eh.name = e.name, eh.job_id = e.job_id, eh.salary = e.salary WHEN NOT MATCHED THEN INSERT INTO emp_hist VALUES (e.employees_id, e.name, e.job_id, e.salary);
Evaluatethefollowingfunctioncode：CREATEFUNCTIONget_dept_avg（dept_idNUMBER）RETURNNUMBERRESULT_CACHERELIES_ON（EMPLOYEES）ISavgsalNUMBER（6）；BEGINSELECTAVG（SALARY）INTOavgsalFROMEMPLOYEESWHEREDEPARTMENT_ID=dept_id；RETURNavgsal；ENDget_dept_avg；Whichstatementistrueregardingtheabovefunction？（）A.ThecachedresultbecomesinvalidwhenanystructuralchangeisdonetotheEMPLOYEEStable.B.Ifthefunctionexecutionresultsinanunhandledexception，theexceptionresultisalsostoredinthecache.C.Eachtimethefunctionisinvokedinadifferentsession，thecurrentresultintheresultcachegetsoverwritten.D.Ifthefunctionisinvokedwithadifferentparametervalue，theexistingresultintheresultcache getsoverwrittenbythelatestvalue.
After __________ (examine) the lady, the doctor suggested that his back was badly hurt in the accident.
YouneedtoimportalldefinitionsofobjectsbelongingtotheTS_EMPLOYEEStablespacebyusingtheexportfileexpdat.dmp.Whichimportstatementiscorrect?() A.imphr/hrTABLES=（ts_employees）rows=yB.impsystem/managerFROMUSER=hrfile=expdat.dmpC.imphr/hrTRANSPORT_TABLESPACE=yfile=expdat.dmpD.impsystem/managerTRANSPORT_TABLESPACE=yTABLESPACE=ts_employees
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