有两个表:
表格名称:门票
+-------+---------+---------+-------------------+
| id | title | closed | param |
+-------+--------------+------------+-----------+
| 1 | test1 | 0 | 1 |
| 2 | test2 | 1 | 1 |
| 3 | test3 | 0 | 1 |
表名:ticket_event
+-------+---------+---------+-----------------+
| id | ticket_id | event | date |
+-------+--------------+----------+-----------+
| 1 | 1 | OPENED | |
| 2 | 1 | CLOSED | |
| 3 | 2 | OPENED | |
+-------+--------------+----------+-----------+
我需要获取每个票证的最新记录ticket_event。结果应为:
test1 CLOSED
test2 OPENED
test3 NULL
我尝试过此代码,但获得了[[ticket_event:]的所有记录SELECT t1.title as t1Title, t2.event as t2Event FROM ticket t1 LEFT JOIN ticket_event t2 ON t1.id = t2.ticket_id
有两个表:表名称:票证+ ------- + --------- + --------- + ---------- --------- + | id |标题|关闭参数| + ------- + -------------- + ------------ + ----------- + | 1 ...
OPENED
列只有两个可能的值CLOSED
和event
(和NULL),则可以按故障单分组并获得每个事件的最小值,因为CLOSED
被认为小于[ C0]: