text: -- https://data.stackexchange.com/stackoverflow/query/949/what-is-my-accepted-answer-percentage-rate
  -- What is my accepted answer percentage rate
  -- On avg how often are answers I give, accepted
  
  DECLARE @UserId int;
  SET @UserId = (SELECT TOP (1) Id FROM dbo.Users ORDER BY NEWID());
  
  SELECT /* What is my accepted answer percentage rate */
      (CAST(Count(a.Id) AS float) / (SELECT Count(*) FROM Posts WHERE OwnerUserId = @UserId AND PostTypeId = 2) * 100) AS AcceptedPercentage
  FROM
      Posts q
    INNER JOIN
      Posts a ON q.AcceptedAnswerId = a.Id
  WHERE
      a.OwnerUserId = @UserId
    AND
      a.PostTypeId = 2