postgresql:有序的结果

时间:2011-07-08 19:56:50

标签: postgresql recursive-query

我的桌子看起来像是:

 id | user_id | activity_id | activity_type | root_id | is_root | timestamp 
----+---------+-------------+---------------+---------+---------+-----------
  1 |       1 |           1 | text          |       1 |       1 |         5
  2 |       2 |           2 | text          |       1 |       0 |         6
  3 |       3 |           3 | text          |       1 |       0 |        10
  4 |       2 |          10 | text          |      10 |       1 |        50
  5 |       1 |          11 | text          |      10 |       0 |        90
  6 |       3 |          12 | text          |      10 |       0 |       100
  7 |       3 |          20 | text          |      20 |       1 |       190
  8 |       2 |          21 | text          |      20 |       0 |       130
  9 |       3 |          22 | text          |      20 |       0 |       150
 10 |       3 |          22 | text          |      20 |       0 |       150
 11 |       3 |          22 | text          |      20 |       0 |       150

我想要一个像

这样的外出
 id | user_id | activity_id | activity_type | root_id | is_root | timestamp 
----+---------+-------------+---------------+---------+---------+-----------
  7 |       3 |          20 | text          |      20 |       1 |       120
  8 |       2 |          21 | text          |      20 |       0 |       130
 11 |       3 |          22 | text          |      20 |       0 |       150
  9 |       3 |          22 | text          |      20 |       0 |       150
 10 |       3 |          22 | text          |      20 |       0 |       150
  4 |       2 |          10 | text          |      10 |       1 |        50
  5 |       1 |          11 | text          |      10 |       0 |        90
  6 |       3 |          12 | text          |      10 |       0 |       100
  1 |       1 |           1 | text          |       1 |       1 |         5
  2 |       2 |           2 | text          |       1 |       0 |         6
  3 |       3 |           3 | text          |       1 |       0 |        10

root_id应该放在一个组中,该组的第一行应该有is_root = 1.这些组应该根据根DESC的时间戳进行排序,但是根目录的子节点应该排序为ASC(基于时间戳)

The relevant columns for the question is root_id, is_root, timestamp

感谢任何帮助。

由于

2 个答案:

答案 0 :(得分:2)

你在说这个吗?

ORDER BY root_id DESC, is_root DESC, timestamp

答案 1 :(得分:2)

order by root_id desc, is_root desc, timestamp asc

应该做的伎俩。