Each duplicate question has up to three other questions as the non-duplicate posts. This query finds the posts that duplicate questions point to. It mostly works, but no guarantees.
Q&A for community managers, administrators, and moderators
create table #Dupes (Dupe INT, Targets VARCHAR(255))
insert into #Dupes
select top 200 PostId as [Post Link],
-- Grab text from after the first '[' to the first ',' or ']'
CASE WHEN charindex(']', Text) < charindex(',', Text) THEN
ELSE charindex(',', Text) END
- charindex('[', Text) - 1) as FirstDupeTarget
from PostHistory h
where PostHistoryTypeId = 10
and Comment in (1, 101)
order by h.CreationDate desc