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tableA

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-----------------------------------
2016-01-01 07:00:00 21.9
2016-01-01 08:00:00 21.9
2016-01-01 09:00:00 22.1
2016-01-01 10:00:00 21.9
2016-01-02 07:00:00 22.2
2016-01-02 08:00:00 22.9
2016-01-02 09:00:00 22.5


tableB

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-----------------------------------
2016-01-01 09:00:00 20
2016-01-02 09:00:00 15
2016-01-03 09:00:00 29
2016-01-04 09:00:00 30


tableC

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---------------------------------------------
2016-01-01 07:00:00 21.9 NULL NULL
2016-01-01 08:00:00 21.9 NULL NULL
2016-01-01 09:00:00 22.1 20 0.9
2016-01-01 10:00:00 21.9 NULL NULL
2016-01-02 07:00:00 22.2 NULL NULL
2016-01-02 08:00:00 22.9 NULL NULL
2016-01-02 09:00:00 22.5 15 0.7


tableD

¤é´Á ¸ê®ÆA ¸ê®ÆB «Y¼Æ ¸ê®ÆC
-------------------------------------------------------
2016-01-01 07:00:00 21.9 NULL 0.9 19.71
2016-01-01 08:00:00 21.9 NULL 0.9 19.71
2016-01-01 09:00:00 22.1 20 0.9 20
2016-01-01 10:00:00 21.9 NULL 0.9 19.71
2016-01-02 07:00:00 22.2 NULL 0.7 15.54
2016-01-02 08:00:00 22.9 NULL 0.7 16.03
2016-01-02 09:00:00 22.5 15 0.7 15

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