复杂的MySQL查询，变量填充

Question

我有一个包含列的表：

AnswerID，OwnerUserID，CreationDate

如何使用OwnerUserID已发布的答案总数填充标题为（AnswersPosted）的第四列，直到为该AnswerID列出CreationDate？

编辑：

下面是表格应该是什么样子的示例。 （抱歉，我刚刚加入时无法发布图片...）我有兴趣让最后一栏显示所有正确的数字。谢谢！

Answer 1

使用此解决方案：

SELECT a.AnswerID,
       a.OwnerUserID,
       a.CreationDate,
       b.cnt AS AnswersPosted
FROM   tbl a
JOIN   (
       SELECT    a.OwnerUserID,
                 a.CreationDate,
                 COUNT(b.OwnerUserID) AS cnt
       FROM      tbl a
       LEFT JOIN tbl b ON a.OwnerUserID  = b.OwnerUserID
                      AND b.CreationDate < a.CreationDate
       GROUP BY  a.OwnerUserID,
                 a.CreationDate
       ) b ON a.OwnerUserID  = b.OwnerUserID
          AND a.CreationDate = b.CreationDate

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SQLFiddle Demo