Using PIVOT with SQL Server without Aggregate function - sql-server

Question

I'm stuck on using PIVOT in a simple example (which I give in entirety below). Full disclosure, I got this from https://www.hackerrank.com/. I picked it precisely because I want to get more familiar with PIVOT and this looked like a simple example! I've looked at numerous posts on the subject, and have been using this to crib off: https://social.msdn.microsoft.com/Forums/sqlserver/en-US/b76a4668-d0c3-4c51-8d86-117d5c181e69/pivot-without-aggregate-function?forum=transactsql but don't seem to be able to get things quite right. Here is the table:
TABLE OCCUPATIONS
Name Occupation
Samantha Doctor
Julia Actor
Maria Actor
Meera Singer
Ashley Professor
Ketty Professor
Christeen Professor
Jane Actor
Jenny Doctor
Priya Singer
The task is to have the output with columns Doctor, Professor, Singer or Actor (in that order). If you run out of data for one or more columns, put NULL. Here is the expected output (copied directly from the site).
Jenny Ashley Meera Jane
Samantha Christeen Priya Julia
NULL Ketty NULL Maria
As an aside, it appears they want the results without column headers (I'm not sure!).
Here is the latest iteration of what I have tried:
SELECT [Doctor], [Professor],[Singer], [Actor]
FROM
(SELECT [Name], [Occupation] from OCCUPATIONS) as pvtsource
PIVOT
( MAX([Name]) FOR [Occupation] IN ([Doctor], [Professor],[Singer], [Actor]) ) AS p
and it yields:
Doctor Professor Singer Actor
Samantha Ketty Priya Maria
I'm not surprised by this incorrect result. After all, I did say in my query MAX. I assume it's just picking the MAX name for each profession based on the alphabetical sort. Maria is a "bigger" actor than Julia or Jane for example if you based it on the alphabet. But when I remove the MAX, I get an error ("Incorrect syntax..."). How does one do this?
Thanks!
Bonus questions
1. Good, gentle, articles to PIVOT? I clearly haven't gotten it through my thick head. Eventually, I do want to be able to do more complicated pivots where I SUM or take MAX.
2. How to display results without column headers?
3. I'd also be interested in how to do this without PIVOT if there is a simple way.

Answer 1

You need to "FEED" the pivot with an X-Axis,Y-Axis and a Value. We create a row key via dense_rank()
Example
Declare #YourTable Table ([Name] varchar(50),[Occupation] varchar(50)) Insert Into #YourTable Values
('Samantha','Doctor')
,('Julia','Actor')
,('Maria','Actor')
,('Meera','Singer')
,('Ashley','Professor')
,('Ketty','Professor')
,('Christeen','Professor')
,('Jane','Actor')
,('Jenny','Doctor')
,('Priya','Singer')
Select *
from (Select *
,RN = dense_rank() over (partition by occupation order by name)
From #YourTable
) src
Pivot (max(Name) for Occupation in ([Doctor], [Professor],[Singer], [Actor]) ) pvt
Returns
RN Doctor Professor Singer Actor
1 Jenny Ashley Meera Jane
2 Samantha Christeen Priya Julia
3 NULL Ketty NULL Maria
NOTE:
If you don't want RN in your results, rather than the top SELECT *, you can specify the desired columns
SELECT [Doctor], [Professor],[Singer], [Actor]
From (...) src
Pivot (...) pvt
EDIT - Commentary
If you run the inner query
Select *
,RN = dense_rank() over (partition by occupation order by name)
From #YourTable
Order By RN
You'll get
Name Occupation RN
Jane Actor 1
Jenny Doctor 1
Ashley Professor 1
Meera Singer 1
Priya Singer 2
Christeen Professor 2
Samantha Doctor 2
Julia Actor 2
Maria Actor 3
Ketty Professor 3
RN becomes the Y-Axis, Occupation becomes the X-Axis and Name is the value.
Pivots by design are aggregates, therefore we just need a Y-Axis to perform the group by.