View the Exhibit and examine the structure of the EMPLOYEES and JOB_HISTORY tables.
The query should display the employee IDs of all the employees who have held the job SA_MAN at any time during their tenure.
Choose the correct SET operator to fill in the blank space and complete the following query.
SELECT employee_id
FROM employees
WHERE job_id = ‘SA_MAN’
____________ SELECT employee_id
FROM job_history
WHERE job_id=’SA_MAN’;
A.
UNION
B.
MINUS
C.
INTERSECT
D.
UNION ALL
select * from tt1
union
select * from tt2;
select * from tt1
union all
select * from tt2 order by 1;
select * from tt1
INTERSECT
select * from tt2 order by 1;
select * from tt1
minus
select * from tt2 order by 1;
If you use INTERSECT, only records from both table with same employee ID would display.
If UNION ALL, will have duplicate employees from both table with same ID.