SQL: Multiple SELECTs instead of JOIN - sql-server

Question

I am not completely new to SQL, but this time I am slow on the uptake.
For a data export, I have to select some user data including two JOINs. The data is not related, I just need both information in one export sheet.
I have created a example. The column groupname is from one JOIN and the column course from the other JOIN:
╔════╦═══════════╦══════════╦═══════════╦════════════╗
║ id ║ firstname ║ lastname ║ groupname ║ course ║
╠════╬═══════════╬══════════╬═══════════╬════════════╣
║ 1 ║ John ║ Doe ║ Manager ║ Management ║
║ 1 ║ John ║ Doe ║ CEO ║ Management ║
║ 1 ║ John ║ Doe ║ Manager ║ Logistics ║
║ 1 ║ John ║ Doe ║ CEO ║ Logistics ║
║ 1 ║ John ║ Doe ║ Manager ║ Leadership ║
║ 1 ║ John ║ Doe ║ CEO ║ Leadership ║
╚════╩═══════════╩══════════╩═══════════╩════════════╝
Due to the nature of JOINS; the groupname-column is duplicated now several times. But what I actually want, is something like this:
╔════╦═══════════╦══════════╦═══════════╦════════════╗
║ id ║ firstname ║ lastname ║ groupname ║ course ║
╠════╬═══════════╬══════════╬═══════════╬════════════╣
║ 1 ║ John ║ Doe ║ Manager ║ ║
║ 1 ║ John ║ Doe ║ CEO ║ ║
║ 1 ║ John ║ Doe ║ ║ Management ║
║ 1 ║ John ║ Doe ║ ║ Logistics ║
║ 1 ║ John ║ Doe ║ ║ Leadership ║
╚════╩═══════════╩══════════╩═══════════╩════════════╝
I guess, doing two SELECT-Statements consecutively would be the better option. Unfortunately, the original query with JOINS and where-Arguments has like 25 lines of code, so I would not like to duplicate it.
Is there a way to achieve my way of output more easily then doing for example a UNION with two long queries (see below for simple example in this case)?
SELECT u.[id]
,[firstname]
,[lastname]
,groupname
,'' AS course
FROM [dbo].[users] u
JOIN dbo.groups g ON u.id = g.userId
UNION ALL
SELECT u.[id]
,[firstname]
,[lastname]
,'' AS groupname
,course
FROM [dbo].[users] u
JOIN dbo.courses c ON u.id = c.userId

Answer 1

You could create a Table-Valued UDF with the query in question and then make a UNION ALL with the two UDFs
Pro:
- Much shorter Query:
SELECT * FROM [MY_UDF](Param 1, Param 2, ...)<br/>
UNION ALL<br/>
SELECT * FROM [MY_UDF](Different Param 1, Different Param 2, ...)
Con:
- You have to create the table valued UDF.
Otherwise: I think QUERY_1 UNION ALL QUERY_2 is probably the way to go.

Answer 2

I think their is a lot of way to solve your problem. I will give you the best way I can think of.
First Solution : Simply use a WITH not to repeat your common part query as follow:
WITH CommonPart (id, firstname, lastname)
AS
(
Select id, firstname, lastname
From [dbo].[users]
-- Eventually a filter ...
)
SELECT cp.*
, g.groupname
, '' AS course
FROM CommonPart cp
JOIN dbo.groups g ON cp.id = g.userId
UNION ALL
SELECT cp.*
,'' AS groupname
,c.course
FROM CommonPart cp
JOIN dbo.courses c ON cp.id = c.userId
Second Solution : You can Insert null values into courses and groups and use a simple LEFT JOIN. But I don't like this second solution.
EDIT: After Insert of null values, it would look like:
Select u.id,
u.firstname,
u.lastname,
g.groupname,
c.course
From [dbo].[users] u
Left Join [dbo].[groups] g ON g.userId = u.id
Left Join [dbo].[courses] c ON c.userId = u.id
Where (g.groupname IS NULL and c.course IS NOT NULL)
OR (g.groupname IS NOT NULL and c.course IS NULL)