多条件选择语句

Question

I've written some code (below) which is trying to select a Job Title and the number of employees assigned to the job title, if it's OrganizationLevel is beneath 3.

I am then trying to insert another couple of conditions. When the OrganizationLevel is beneath 2, the Job Title becomes upper case.

But I am struggling to implement a second condition in to this SQL. When the OrganizationLevel = 1, the Job Title should display 'MANAGING DIRECTOR'.

Can someone please help me in achieving this? Here's what I have so far:

with T as( SELECT IIF ( OrganizationLevel < 2, UPPER ( IIF ( OrganizationLevel=1, 'MANAGING DIRECTOR', JobTitle )), JobTitle ) AS JobTitle , OrganizationLevel
from HumanResources.Employee)
select count(*) AS NumOfEmp,JobTitle from T 
where OrganizationLevel < 3 group by JobTitle order by JobTitle;

Thank you.

Answer 1

You should try the CASE expression:

with T as( 
SELECT case
        when OrganizationLevel = 1 then 'MANAGING DIRECTOR'
        when OrganizationLevel < 2 then upper(JobTitle)
        else JobTitle 
    end AS JobTitle,
    OrganizationLevel
from HumanResources.Employee)

select count(*) AS NumOfEmp, JobTitle 
from T 
where OrganizationLevel < 3 
group by JobTitle 
order by JobTitle;