我想以这样的方式返回数据，即如果代码具有连续的活动日期和结束日期，则数据应给出最小活动日期和最大结束日期，但如果代码已停止，则应显示两个日期
例如桌子
+----+------+---------------+------------+
|Code| Decri| Active Date |End Date |
+----+------+---------------+------------+
|1000| ABC | 1/1/2011 | 30/6/2011 |
|1000| ABC | 1/7/2011 | 30/6/2012 |
|1000| ABC | 1/7/2012 | 30/6/2013 |
|1001| ABC | 1/7/2013 | 30/6/2014 |
|1001| ABC |12/20/2015 |12/20/2017 |
|1003| ABC | 1/1/2011 |30/6/2011 |
|1003| ABC | 1/7/2012 |30/6/2013 |
|1003| ABC | 1/7/2014 |30/6/2015 |
|1003| ABC | 1/7/2015 |12/20/2017 |
+----+------+---------------+------------+
欲望输出
+----+------+---------------+------------+
|Code| Decri| Active Date |End Date |
+----+------+---------------+------------+
|1000| …