Yes, there are a couple of those inconsistencies. I've created the following query to find those cases where the
acceptedanswerid on the question links to an answer that has a different
select q.id as [Post Link]
, (select count(*)
where postid = q.id and posthistorytypeid = 37) as [Source migrated]
, a.id as [Post Link]
, (select count(*)
where postid = a.id and posthistorytypeid = 38) as [Dest migrated]
when a.deletiondate is not null
from posts q
inner join postswithdeleted a on a.id = q.acceptedanswerid
where q.id <> a.parentid
The query outputs the following columns:
- Question Link
- Question Creationdate
- # Merge Source events in Posthistory
- Answer Link
- Answer CreationDate
- # Merge Destination events in Posthistory.
When you glance over the results you see the following patterns:
- Merge source present and Merge Destination present.
- Merge source present and deleted answer
- Merge source absent and deleted answer
- Merge source absent and active answer, Merge destination absent
For the cases where the merge source is present it always means the question was merged into another question. In those cases I tend to disagree that the record for the question should be fixed. It kind of keeps track of what the original OP choose as the accepted answer, which is valuable info in some sense.
For the cases where the merge source is absent we see the left overs of a race condition that once existed. It becomes manifest when one Q/A has multiple accepted questions or where answers have an accept vote in their history but isn't shown.
Here are the bug reports that describe the issue:
Answer accepted twice
Accepted answer reward +15 awarded twice!
Bug: Awarded double rep for accepted answer
Multiple accepted answers to a question?
For the above cases where I was sure a moderator could rectify the issue I've flagged or will be flagging the question or answer. I delete voted one question because it was about PHP.
tl;dr; The merge stubs shouldn't be fixed, the remaining errors can be rectified with flags and a moderator action.