如何在一张桌子上连接五张桌子？

Question

我有 5 个表是设备日志，表是一样的，只是按月份划分，你需要将它们粘合到一个表中，并使用 DEVICES_ACTIVE 将其连接到主键。

     1. Table DEVICES_ACTIVE
         DEVICE_ID  NUMBER(38,0)    PK

     2. Table DJ_05_2014
        DEVICE_ID NUMBER(38,0) PK
        START TIMESTAMP
        STOP TIMESTAMP

     3. Table DJ_06_2014
        DEVICE_ID NUMBER(38,0) PK
        START TIMESTAMP
        STOP TIMESTAMP

     4. Table DJ_07_2014
        DEVICE_ID NUMBER(38,0) PK
        START TIMESTAMP
        STOP TIMESTAMP
......................

Answer 1

select ...
  from devices_active
  join (select ... from dj_07_2014 union all
        select ... from dj_06_2014 union all
        select ... from dj_05_2014
       ) using(device_id);