mysql - BigQuery - 根据匹配值或时间戳合并三个表

Question

类似于问题BigQuery combine tables based on closest timerstamp and matching value

我有三个表，对于表numberTwo的每一行，我需要在表numberOne中获取具有相同提示>cod 值，以及在比较 time1 和 time2 时具有最接近时间的值。如果表numberOne中没有出现cod，它会尝试获取与表中的cod匹配的提示数字三

为了更容易理解我需要做的事情是:

表号一:

|  id |  cod  |   hint  |           time1         |
---------------------------------------------------
|  1  |  ABC  |    V    | 2016-11-03 18:00:00 UTC |
|  2  |  ABC  |    W    | 2016-11-03 12:00:00 UTC |
|  3  |  CDE  |    X    | 2016-11-03 19:00:00 UTC |
|  4  |  CDE  |    Y    | 2016-11-03 19:30:00 UTC |
|  5  |  EFG  |    Z    | 2016-11-03 18:00:00 UTC |

表号二

|  id |  cod  |   value  |         time2           |
----------------------------------------------------
|  1  |  ABC  |   xyz2   | 2016-11-03 18:20:00 UTC |
|  2  |  FHK  |   h323   | 2016-11-03 11:30:00 UTC |
|  3  |  ABC  |   rewq   | 2016-11-03 09:00:00 UTC |
|  4  |  IJK  |   abce   | 2016-11-03 19:10:00 UTC |

表号三

|  id |  cod  |   hint   |
--------------------------
|  1  |  FHK  |   tes1   |
|  2  |  IJK  |   tes2   |
|  3  |  MNK  |   tes3   |
|  4  |  MOP  |   tes4   |

因此，对于表 numberTwo 的 row #1，我将使用 cod: ABC 获取表 numberOne 中的所有行强>

|  1  |  ABC  |    V    | 2016-11-03 18:00:00 UTC |
|  2  |  ABC  |    W    | 2016-11-03 12:00:00 UTC |

在这些之间，我会得到与 time2 最接近的时间戳:

|  1  |  ABC  |    V    | 2016-11-03 18:00:00 UTC |

如果cod未出现在表numberOne中，则它与表numberThree匹配。 numberOne 和 numberThree 中的代码是唯一的。因此，两个表中不会出现相同的代码。因此它可以首先尝试匹配表numberThree。

处理完每一行后，我将得到一个像这样的表:

所需表格

|  id |  cod  |   hint  |   value  |         time2           |
--------------------------------------------------------------
|  1  |  ABC  |    V    |   xyz2   | 2016-11-03 18:20:00 UTC |
|  2  |  FHK  |   tes1  |   h323   |                         |
|  3  |  ABC  |    W    |   rewq   | 2016-11-03 09:00:00 UTC |
|  4  |  IJK  |   tes2  |   abce   |                         |

Answer 1

尝试下面

WITH 
/*
TableNumberOne AS (
  SELECT 1 AS id, 'ABC' AS cod, 'V' AS hint, TIMESTAMP '2016-11-03 18:00:00 UTC' AS time1 UNION ALL
  SELECT 2 AS id, 'ABC' AS cod, 'W' AS hint, TIMESTAMP '2016-11-03 12:00:00 UTC' AS time1 UNION ALL
  SELECT 3 AS id, 'CDE' AS cod, 'X' AS hint, TIMESTAMP '2016-11-03 19:00:00 UTC' AS time1 UNION ALL
  SELECT 4 AS id, 'CDE' AS cod, 'Y' AS hint, TIMESTAMP '2016-11-03 19:30:00 UTC' AS time1 UNION ALL
  SELECT 5 AS id, 'EFG' AS cod, 'Z' AS hint, TIMESTAMP '2016-11-03 18:00:00 UTC' AS time1 
),
TableNumberTwo AS (
  SELECT 1 AS id, 'ABC' AS cod, 'xyz2' AS value, TIMESTAMP '2016-11-03 18:20:00 UTC' AS time2 UNION ALL
  SELECT 2 AS id, 'FHK' AS cod, 'h323' AS value, TIMESTAMP '2016-11-03 11:30:00 UTC' AS time2 UNION ALL
  SELECT 3 AS id, 'ABC' AS cod, 'rewq' AS value, TIMESTAMP '2016-11-03 09:00:00 UTC' AS time2 UNION ALL
  SELECT 4 AS id, 'IJK' AS cod, 'abce' AS value, TIMESTAMP '2016-11-03 19:10:00 UTC' AS time2 
),
TableNumberThree AS (
  SELECT 1 AS id, 'FHK' AS cod, 'test1' AS hint UNION ALL
  SELECT 2 AS id, 'IJK' AS cod, 'test2' AS hint UNION ALL
  SELECT 3 AS id, 'MNK' AS cod, 'test3' AS hint UNION ALL
  SELECT 4 AS id, 'MOP' AS cod, 'test4' AS hint 
),
*/
tempTable AS (
  SELECT 
    t2.id, t2.cod, t2.value, t2.time2, t1.hint, 
    ROW_NUMBER() OVER(PARTITION BY t2.id, t2.cod, t2.value 
                      ORDER BY ABS(TIMESTAMP_DIFF(t2.time2, t1.time1, SECOND))) AS win
  FROM TableNumberTwo AS t2
  LEFT JOIN TableNumberOne AS t1
  ON t1.cod = t2.cod
)
SELECT 
  t1.id, t1.cod, IFNULL(t1.hint, t2.hint) AS hint, value, 
  IF(t1.hint IS NULL, NULL, time2) as time2
FROM tempTable AS t1
LEFT JOIN TableNumberThree AS t2
ON t1.cod = t2.cod AND t1.hint IS NULL
WHERE win = 1