WITH FirstQs(QCreationDate, PostId, UserId)
AS
(
SELECT
MIN(p.CreationDate) [CreationDate]
,MIN(p.Id) [PostId]
,MIN(u.Id) [UserId]
FROM Users u JOIN Posts p ON u.Id = p.OwnerUserId
WHERE (p.PostTypeId = 1)
GROUP BY u.Id
),
FirstQsA(ACreationDate, APostId)
AS
(
SELECT
MIN(p.CreationDate) [ACreationDate]
,MIN(p.Id) [APostId]
FROM Posts p, FirstQs
WHERE (p.PostTypeId = 2 AND p.ParentId = PostId)
)
SELECT UserId
,MIN(QCreationDate)
,MIN(ACreationDate)
,PostId[Post Link]
,APostId[Post Link]