You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.
The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.
The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.
Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.
The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.
The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.
第1题:
Examine the structure of the EMPLOYEES table:EMPLOYEE_ID NUMBER NOT NULLEMP_NAME VARCHAR2(30)JOB_ID VARCHAR2(20) DEFAULT ‘SA_REP‘SAL NUMBERCOMM_PCT NUMBERMGR_ID NUMBERDEPARTMENT_ID NUMBERYou need to update the records of employees 103 and 115. The UPDATE statement you specify should update the rows with the values specified below:JOB_ID: Default value specified for this column definition.SAL: Maximum salary earned for the job ID SA_REP.COMM_PCT: Default value specified for this commission percentage column, if any. If no default value is specified for the column, the value should be NULL. DEPARTMENT_ID: Supplied by the user during run time through substitution variable.Which UPDATE statement meets the requirements?()
A. UPDATE employees SET job_id = DEFAULT AND Sal = (SELECT MAX(sal) FROM employees WHERE job_id = ‘SA_REP‘) AND comm_pct = DEFAULT AND department_id = &did WHERE employee _id IN (103,115);
B. UPDATE employees SET job_id = DEFAULT AND Sal = MAX(sal) AND comm_pct = DEFAULT OR NULL AND department_id = &did WHERE employee_id IN (103,115) AND job _ id = ‘SA_ REP‘;
C. UPDATE employees SET job_id = DEFAULT, Sal = (SELECT MAX(sal) FROM employees WHERE job_id = ‘SA_REP‘), comm_pct = DEFAULT, department_id = &did WHERE employee_id IN (103,115);
D. UPDATE employees SET job_id = DEFAULT, Sal = MAX(sal), comm_pct = DEFAULT, department_id = &did WHERE employee_id IN (103,115) AND job _ id = ‘SA_ REP‘;
E. UPDATE employees SET job_id = DEFAULT, Sal = (SELECT MAX(sal) FROM employees WHERE job_id = ‘SA_REP‘) comm_pct = DEFAULT OR NULL, department_id = &did WHERE employee_id IN (103,115);
第2题:
Click the Exhibit button and examine the data in the EMPLOYEES table.On 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.
第3题:
A. CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) NOT NULL CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);
B. CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
C. CREATE TABLE EMP (empno NUMBER(4) ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));
D. CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp deptno fk REFERENCES dept (deptno));
第4题:
Which SQL statement defines the FOREIGN KEY constraint on the DEPTNO column of the EMP table?()
第5题:
Examine the structure if the EMPLOYEES table: Column name Data Type Remarks EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) NOT NULL SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You need to create a view called EMP_VU that allows the user to insert rows through the view. Which SQL statement, when used to create the EMP_VU view, allows the user to insert rows? ()
第6题:
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7题:
Examine the structure of the EMPLOYEES and DEPARTMENTS tables: EMPLOYEESColumn name Data type Remarks EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2 (30) JOB_ID VARCHAR2 (20) SALARY NUMBER MGR_ID NUMBER References EMPLOYEE_ID COLUMN DEPARTMENT ID NUMBER Foreign key to DEPARTMENT ID column of the DEPARTMENTS table DEPARTMENTSColumn name Data type Remarks DEPARTMENT_ID NUMBER NOT NULL, Primary Key DEPARTMENT_NAME VARCHAR2(30) MGR_ID NUMBER References MGR_ID column of the EMPLOYEES table Evaluate this SQL statement: SELECT employee_id, e.department_id, department_name, salary FROM employees e, departments d WHERE e. department_id = d.department_id; Which SQL statement is equivalent to the above SQL statement? ()
第8题:
Examine the data in the EMPLOYEES table.On 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: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.
第9题:
You created a view called EMP_DEPT_VU that contains three columns from the EMPLOYEES and DEPARTMENTS tables: EMPLOYEE_ID, EMPLOYEE_NAME AND DEPARTMENT_NAME. The DEPARTMENT_ID column of the EMPLOYEES table is the foreign key to the primary key DEPARTMENT_ID column of the DEPARTMENTS table. You want to modify the view by adding a fourth column, MANAGER_ID of NUMBER data type from the EMPLOYEES tables. How can you accomplish this task?()
第10题:
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) DEFAULT 'SA_REP' SAL NUMBER COMM_PCT NUMBER MGR_ID NUMBER DEPARTMENT_ID NUMBER You need to update the records of employees 103 and 115. The UPDATE statement you specify should update the rows with the values specified below: JOB_ID: Default value specified for this column definition. SAL: Maximum salary earned for the job ID SA_REP. COMM_PCT: Default value specified for this commission percentage column, if any. If no default value is specified for the column, the value should be NULL. DEPARTMENT_ID: Supplied by the user during run time through substitution variable. Which UPDATE statement meets the requirements?()