Is there any way we can find the top users for a tag given in a particular time period? For example, someone was very active and rose to top 10 for certain tags in 2014 but then changed technologies or maybe went inactive. Information like this could be really helpful to be put on someone's resume.
The easy way would be to see if the "Top Users" page was archived somewhere. Here is an example of such a page. But you don't always get lucky with that.
Data dumps for most (but not all) of Stack Overflow's history can be found here.
You then should be able to run the following query by conradfrix on that data to get the rankings:
-- tag rankings -- Calculates rank by tag. Make tag name empty spaces for all tags DECLARE @tagName varchar(255) DECLARE @tagInput bit SET @tagname = rtrim(##TagName:string##) IF RTRIM(@tagname) = '' SET @tagInput = 0 ELSE SET @tagInput = 1 ;WITH UserTagScores as (SELECT a.OwnerUserId, t.TagName, SUM(CASE v.VoteTypeID WHEN 2 THEN 1 WHEN 3 THEN -1 END) as score FROM votes v INNER JOIN Posts a ON v.PostID = a.ID INNER JOIN Posts q ON a.parentId = q.id INNER JOIN PostTags pt ON q.id = pt.PostId INNER JOIN Tags T ON pt.TagId = t.id WHERE v.voteTypeId in (2,3) -- Up and down votes and a.PostTypeID = 2 -- Answers only AND (a.CommunityOwnedDate is null or a.CommunityOwnedDate > v.CreationDate) AND (@tagInput = 0 or t.TagName = @TagName) AND a.OwnerUserId is not null GROUP BY a.OwnerUserId, t.TagName) , userTagRank as ( SELECT TagName, OwnerUserId as [User Link], rank() over (partition by TagName order by score desc) rank FROM UserTagScores WHERE score > 5) SELECT * FROM userTagRank ORDER BY TagName