INSERT INTO SELECT with multiple CASE WHEN - sql-server

Question

I am trying to insert into table using select from another table with multiple case scenarios. Each person has more than one value, which gives multiple rows in the jointable. I want to select col2 based on col1 from the jointable.
The outcome so far, is 3 line of same person, 1 of the 3 values in each row.
See result here
INSERT INTO #temp (Name, WageNo, Tiltraedelses_dato, Jubilaeum ,Sabbatical, Anciennitet)
SELECT
e.FirstName,
e.WageSystemKey,
e.[StartDate],
CASE WHEN v.EmployeeCustomColumnId = 2 THEN v.Value END,
CASE WHEN v.EmployeeCustomColumnId = 3 THEN v.Value END,
CASE WHEN v.EmployeeCustomColumnId = 1 THEN v.Value END
FROM Employees e
LEFT JOIN EmployeeCustomValue v on e.EmployeeId = v.EmployeeId
SELECT * FROM #temp

Answer 1

I think you need a group by with conditional aggregation, something like this
INSERT INTO #temp (Name, WageNo, Tiltraedelses_dato, Jubilaeum ,Sabbatical, Anciennitet)
SELECT
e.FirstName,
e.WageSystemKey,
e.[StartDate],
max(CASE WHEN v.EmployeeCustomColumnId = 2 THEN v.Value END),
max(CASE WHEN v.EmployeeCustomColumnId = 3 THEN v.Value END),
max(CASE WHEN v.EmployeeCustomColumnId = 1 THEN v.Value END)
FROM Employees e
LEFT JOIN EmployeeCustomValue v on e.EmployeeId = v.EmployeeId
group by e.FirstName,
e.WageSystemKey,
e.[StartDate]

Answer 2

Here are a couple of other ways to go about this.
INSERT INTO #temp (Name, WageNo, Tiltraedelses_dato, Jubilaeum ,Sabbatical, Anciennitet)
SELECT
e.FirstName,
e.WageSystemKey,
e.[StartDate],
v2.Value,
v3.Value,
v1.Value
FROM Employees e
LEFT JOIN EmployeeCustomValue v1 on e.EmployeeId = v1.EmployeeId and v1.EmployeeCustomColumnId = 1
LEFT JOIN EmployeeCustomValue v2 on e.EmployeeId = v2.EmployeeId and v2.EmployeeCustomColumnId = 2
LEFT JOIN EmployeeCustomValue v3 on e.EmployeeId = v3.EmployeeId and v3.EmployeeCustomColumnId = 3
Or
INSERT INTO #temp (Name, WageNo, Tiltraedelses_dato, Jubilaeum ,Sabbatical, Anciennitet)
SELECT FirstName, WageSystemKey, [StartDate],
MAX(Jubilaeum) AS Jubilaeum, MAX(Sabbatical) AS Sabbatical,
MAX(Anciennitet) AS Anciennitet
FROM (SELECT
e.FirstName,
e.WageSystemKey,
e.[StartDate],
CASE WHEN v.EmployeeCustomColumnId = 2 THEN v.Value END AS Jubilaeum,
CASE WHEN v.EmployeeCustomColumnId = 3 THEN v.Value END AS Sabbatical,
CASE WHEN v.EmployeeCustomColumnId = 1 THEN v.Value END AS Anciennitet
FROM Employees e
LEFT JOIN EmployeeCustomValue v on e.EmployeeId = v.EmployeeId) AA
GROUP BY FirstName, WageSystemKey, [StartDate]