单项选择题
Which syntax turns an existing constraint on?（）
A. ALTER TABLE table_name ENABLE constraint_name;
B. ALTER TABLE table_name STATUS = ENABLE CONSTRAINT constraint _ name;
C. ALTER TABLE table_name ENABLE CONSTRAINT constraint _ name;
D. ALTER TABLE table_name TURN ON CONSTRAINT constraint _ name;
相关考题
-
单项选择题
Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: Which statement ensures that a value is displayed in the calculated columns for all employees?（）
A. SELECT last_name, 12*salary* commission_pct FROM emp;
B. SELECT last_name, 12*salary* (commission_pct,0) FROM emp;
C. SELECT last_name, 12*salary*(nvl(commission_pct,0)) FROM emp;
D. SELECT last_name, 12*salary*(decode(commission_pct,0)) FROM emp; -
单项选择题
Examine the description of the EMPLOYEES table: Which statement shows the maximum salary paid in each job category of each department?（）
A. SELECT dept_id, job_cat, MAX(salary) FROM employees WHERE salary > MAX(salary);
B. SELECT dept_id, job_cat, MAX(salary) FROM employees GROUP BY dept_id, job_cat;
C. SELECT dept_id, job_cat, MAX(salary) FROM employees;
D. SELECT dept_id, job_cat, MAX(salary) FROM employees GROUP BY dept_id;
E. SELECT dept_id, job_cat, MAX(salary) FROM employees GROUP BY dept_id, job_cat, salary; -
单项选择题
Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: LAST NAME VARCNAR2(35) NOT NULL SALARY NUMBER(9,2) NOT NULL COMMISION_PCT NUMBER(4,2) Which statement ensures that a value is displayed in the calculated columns for all employees?（）
A. SELECT last_name, 12*salary* commission_pct FROM emp;
B. SELECT last_name, 12*salary* (commission_pct,0) FROM emp;
C. SELECT last_name, 12*salary*(nvl(commission_pct,0)) FROM emp;
D. SELECT last_name, 12*salary*(decode(commission_pct,0)) FROM emp;
