单项选择题

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? （）

A. CREATE VIEW emp_Vu AS SELECT employee_id, emp_name, department_id FROM employees WHERE mgr_id IN (102, 120);
B. CREATE VIEW emp_Vu AS SELECT employee_id, emp_name, job_id department_id FROM employees WHERE mgr_id IN (102, 120);
C. CREATE VIEW emp_Vu AS SELECT department_id, SUM(sal) TOTALSAL FROM employees WHERE mgr_id IN (102, 120) GROUP BY department_ id;
D. CREATE VIEW emp_Vu AS SELECT employee_id, emp_name, job_id, DISTINCT department_id FROM employees;

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热门试题

多项选择题Which three SELECT statements displays 2000 in the format $2,000.00 ? （）

A. SELECT TO CNAR(2000, '$#,###.##') FROM dual;
B. SELECT TO CNAR(2000, '$0,000.00') FROM dual;
C. SELECT TO CNAR(2000, '$9,999.00') FROM dual;
D. SELECT TO CNAR(2000, '$9,999.99') FROM dual;
E. SELECT TO CNAR(2000, '$2,000.00') FROM dual;
F. SELECT TO CNAR(2000, '$N,NNN.NN') FROM dual;

多项选择题For which two constraints does the Oracle Server implicitly create a unique index? （）

A. NOT NULL
B. PRIMARY KEY
C. FOREIGN KEY
D. CHECK
E. UNIQUE