Question

我的Oracle 9i数据库中有这些行。这些行已经过了＆＃39; group＆＃39;列。

ticket_id    | datestamp            | type    | group
1-7323887901 | 22-Apr-14 3:38:14 PM | create  | A
1-7323889625 | 22-Apr-14 3:43:39 PM | create  | A
1-7323889625 | 05-May-14 5:38:37 PM | resolve | A
1-7323889628 | 05-May-14 5:38:37 PM | create  | B
1-7323887901 | 05-May-14 6:13:29 PM | resolve | A

我想创建一个查询来查找带有max created datestamp＆amp;的票证ID。具有最小解决日期戳的票证ID。

基本上我的例外输出如下。（总是期望返回两行）

ticket_id    | datestamp            | type    | group
1-7323889625 | 22-Apr-14 3:43:39 PM | create  | A
1-7323889625 | 05-May-14 5:38:37 PM | resolve | A

THX。

[edit]添加了另一个我要排除

的群组的记录

Answer 1

select * from (
select *
from ticket 
where type = 'create'
order by datestamp desc
) where rownum = 1

union all

select * from (
select *
from ticket 
where type = 'resolved'
order by datestamp 
) where rownum = 1

Answer 2

你可以简单地使用两个不同的选择查询，一个是MAX（）聚合函数，另一个是MIN（）聚合函数，然后用UNION运算符组合两个结果。

或试试这个，

SELECT * FROM table_name 
 WHERE datestamp = (SELECT MAX(datestamp) FROM table_name)
 OR
 WHERE datestamp = (SELECT MIN(datestamp) FROM table_name);

希望这有帮助。

Answer 3

您可以加入子查询。这样的事情会让你开始

select ticketid, type, mindate thedate
from ticket join 
(select min(datestamp) mindate
from ticket
where type = 'create' ) t1 on ticket.datestamp = t1.datestamp
where type = 'create'
union

select ticketid, type, mindate thedate
from ticket join 
(select min(datestamp) mindate
from ticket
where type = 'resolve' ) t2 on ticket.datestamp = t2.datestamp
where type = 'resolve'

如果你有联系，你必须在尝试编写代码之前决定你想要的东西。

Answer 4

SELECT * FROM Tablename
WHERE (date_stamp = (SELECT MAX(date_stamp) FROM Tablename WHERE TYPE='CREATE')
OR
date_stamp = (SELECT MIN(date_stamp) FROM Tablename WHERE TYPE='RESOLVE'))

Answer 5

试试这个：

select t.id from ticket t
 where datestamp = (select max(datestamp) from ticket where type = 'create')
    or datestamp = (select min(datestamp) from ticket where type = 'resolve')

如果您有两个完全相同的日期戳，则无效。你可以使用rownum，但这不是一个好主意。

select t.id from ticket t
 where datestamp = (select max(datestamp) from ticket where type = 'create' and rownum =1)
    or datestamp = (select min(datestamp) from ticket where type = 'resolve' and rownum =1)

查找Max＆amp;记录最小日期戳以查找重叠的期间

5 个答案: