How to pivot table and combine rows based on a condition

Question

I have the following table produced by the following SQL:

select userid, name, sirname, age from Users

I am wondering what would the best way be to convert this to something that looks like:

Would partition by + distinct be the most efficient way of doing this?

Answer 1

SELECT userid, [0] AS name, [1] AS sirname, age
FROM users 
PIVOT
(MAX(name)
FOR sirname IN ([0],[1]))AS p

Answer 2

I would just suggest aggregation:

select userid, max(case when simame = 0 then name end) as name,
       max(case when simmame = 1 then name end) as simame,
       age
from t
group by userid, age;

Answer 3

I'd like to suggest, that the most natural solution would be:

SELECT
    u1.id
    ,u1.name
    ,u2.name as sirname
    ,u1.age
FROM users u1
INNER JOIN users u2 ON u1.id=u2.id and u2.sirname=1
WHERE
  u1.sirname=0

even more so, as this approach can easily be modelled to cope with situations where one of the two names may be missing.