1)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;
2)description of the students table:
sid_id number
start_date date
end_date date
which two function are valid on the start_date column?_________。
a. sum(start_date)
b. avg(start_date)
c. count(start_date)
d. avg(start_date,end_date)
e. min(start_date)
f. maximum(start_date)
3)for which two constraints does the oracle server implicitly create a unique index?______。
a. not null
b. primary
c. foreign key
d. check
e. unique
4)in a select statement that includes a where clause,where is the group by clause placed in the select statement?______。
a. immediately after the select clause
b. before the where clause
c. before the from clause
d. after the order by clause
e. after the where clause
5)in a select statement that includes a where clause,where is the order by clause placed in the select statement?______.
a.immediately after the select clause
b.before the where clause
c.after all clause
d.after the where clause
e.before the from clause