Examine the data in the EMPLOYEES and DEPARTMENTS tables:
EMPLOYEES
EMP_NAME DEPT_ID MGR_ID JOB_ID SALARY
EMPLOYEE_ID
101 Smith 20 120 SA_REP 4000
102 Martin 10 105 CLERK 2500
103 Chris 20 120 IT_ADMIN 4200
104 John 30 108 HR_CLERK 2500
105 Diana 30 108 IT_ADMIN 5000
106 Smith 40 110 AD_ASST 3000
108 Jennifer 30 110 HR_DIR 6500
110 Bob 40 EX_DIR 8000
120 Ravi 20 110 SA*DIR 6500
DEPARTMENTS
DEPARTMENT_ID DEPARTMENT_NAME
10 Admin
20 Education
30 IT
40 Human Resources
Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables:
CREATE TABLE departments
(department_id NUMBER PRIMARY KEY,
department _ name VARCHAR2(30));
CREATE TABLE employees
(EMPLOYEE_ID NUMBER PRIMARY KEY,
EMP_NAME VARCHAR2(20),
DEPT_ID NUMBER REFERENCES
departments(department_id),
MGR_ID NUMBER REFERENCES
employees(employee id),
MGR_ID NUMBER REFERENCES
employees(employee id),
JOB_ID VARCHAR2(15).
SALARY NUMBER);
ON the EMPLOYEES,
On the EMPLOYEES table, EMPLOYEE_ID is the primary key.
MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. DEPT_ID is foreign key to DEPARTMENT_ID column of the DEPARTMENTS table. On the DEPARTMENTS table, DEPARTMENT_ID is the primary key.
Examine this DELETE statement:
DELETE
FROM departments
WHERE department id = 40;
What happens when you execute the DELETE statement?()
第1题:
UserSCOTTwantstoexporthisobjectsusingOracleDataPumpandexecutesthefollowingcommand:$expdpscott/tigerdirectory=EXPORT_DIRdumpfile=scott.dmpinclude=tableinclude=view:"like’%DEPARTMENTS%’"content=DATA_ONLYWhichtaskwouldthecommandaccomplish?()
A.A
B.B
C.C
D.D
E.E
第2题:
已知关系模式R的全部属性集U={A,B,C,D,E,G}及函数依赖集:
F=(AB→C,C→A,BC→D,ACD→B,D→EG,BE→C,CG→BD,CE→AG}求属性集闭包(BD)+
(2) 现有如下两个关系模式:
Employees(Eid,Name,DeptNO)
Departments(DeptNO,DeptName,TotalNumber)
Employees关系模式描述了职工编号、姓名和所在部门编号;Departments关系模式描述了部门编号、名称和职工总
第3题:
A.OracleManagedFilesareusedforthisinstance.
B.TheUSER_DATAtablespaceismanagedusingFET$/UET$tables.
C.TheCOMPATIBLEinitializationparametermustbe9.0.0orhigher.
D.SpacewithinsegmentsintheUSER_DATAtablespaceismanagedwithfreelists.
第4题:
第5题:
检查
A.expect
B.except
C.excuse
D.examine
第6题:
多航向航迹计算求经差
A.Dλ=DeP×Sec起止点的平均纬度
B.Dλ=ƩDeP×Sec到达点纬度
C.Dλ=DeP×Sec起止点的平均经度
D.27.Dλ=ƩDeP×Sec起始点纬度