sql 数组学习(本代码仅仅在bigquery 中复现)

SELECT ARRAY
  (SELECT 1 UNION ALL
   SELECT 2 UNION ALL
   SELECT 3) AS new_array;

+-----------+
| new_array |
+-----------+
| [1, 2, 3] |
+-----------+

SELECT
  ARRAY
    (SELECT AS STRUCT 1, 2, 3
     UNION ALL SELECT AS STRUCT 4, 5, 6) AS new_array;

+------------------------+
| new_array              |
+------------------------+
| [{1, 2, 3}, {4, 5, 6}] |
+------------------------+

WITH items AS
  (SELECT ["coffee", NULL, "milk" ] as list
  UNION ALL
  SELECT ["cake", "pie"] as list)

SELECT list, ARRAY_LENGTH(list) AS size
FROM items
ORDER BY size DESC;

+---------------------------------+------+
| list                            | size |
+---------------------------------+------+
| [coffee, NULL, milk]            | 3    |
| [cake, pie]                     | 2    |
+---------------------------------+------+

WITH items AS
  (SELECT ["coffee", "tea", "milk" ] as list
  UNION ALL
  SELECT ["cake", "pie", NULL] as list)

SELECT ARRAY_TO_STRING(list, '--', 'MISSING') AS text
FROM items;

+--------------------------------+
| text                           |
+--------------------------------+
| coffee--tea--milk              |
| cake--pie--MISSING             |
+--------------------------------+

+-----------------+
| example_array   |
+-----------------+
| [1, 2, 3, 4, 5] |
+-----------------+

SELECT GENERATE_ARRAY(0, 10, 3) AS example_array;

+---------------+
| example_array |
+---------------+
| [0, 3, 6, 9]  |
+---------------+

SELECT GENERATE_ARRAY(10, 0, -3) AS example_array;

+---------------+
| example_array |
+---------------+
| [10, 7, 4, 1] |
+---------------+

SELECT GENERATE_DATE_ARRAY('2016-10-05', '2016-10-08') AS example;

+--------------------------------------------------+
| example                                          |
+--------------------------------------------------+
| [2016-10-05, 2016-10-06, 2016-10-07, 2016-10-08] |
+--------------------------------------------------+

SELECT GENERATE_DATE_ARRAY(
 '2016-10-05', '2016-10-09', INTERVAL 2 DAY) AS example;

+--------------------------------------+
| example                              |
+--------------------------------------+
| [2016-10-05, 2016-10-07, 2016-10-09] |
+--------------------------------------+

SELECT GENERATE_DATE_ARRAY(date_start, date_end, INTERVAL 1 WEEK) AS date_range
FROM (
  SELECT DATE '2016-01-01' AS date_start, DATE '2016-01-31' AS date_end
  UNION ALL SELECT DATE "2016-04-01", DATE "2016-04-30"
  UNION ALL SELECT DATE "2016-07-01", DATE "2016-07-31"
  UNION ALL SELECT DATE "2016-10-01", DATE "2016-10-31"
) AS items;

+--------------------------------------------------------------+
| date_range                                                   |
+--------------------------------------------------------------+
| [2016-01-01, 2016-01-08, 2016-01-15, 2016-01-22, 2016-01-29] |
| [2016-04-01, 2016-04-08, 2016-04-15, 2016-04-22, 2016-04-29] |
| [2016-07-01, 2016-07-08, 2016-07-15, 2016-07-22, 2016-07-29] |
| [2016-10-01, 2016-10-08, 2016-10-15, 2016-10-22, 2016-10-29] |
+--------------------------------------------------------------+

SELECT GENERATE_TIMESTAMP_ARRAY('2016-10-05 00:00:00', '2016-10-07 00:00:00',
                                INTERVAL 1 DAY) AS timestamp_array;

+--------------------------------------------------------------------------+
| timestamp_array                                                          |
+--------------------------------------------------------------------------+
| [2016-10-05 00:00:00+00, 2016-10-06 00:00:00+00, 2016-10-07 00:00:00+00] |
+--------------------------------------------------------------------------+

SELECT GENERATE_TIMESTAMP_ARRAY('2016-10-05 00:00:00', '2016-10-05 00:00:02',
                                INTERVAL 1 SECOND) AS timestamp_array;

+--------------------------------------------------------------------------+
| timestamp_array                                                          |
+--------------------------------------------------------------------------+
| [2016-10-05 00:00:00+00, 2016-10-05 00:00:01+00, 2016-10-05 00:00:02+00] |
+--------------------------------------------------------------------------+

SELECT GENERATE_TIMESTAMP_ARRAY(start_timestamp, end_timestamp, INTERVAL 1 HOUR)
  AS timestamp_array
FROM
  (SELECT
    TIMESTAMP '2016-10-05 00:00:00' AS start_timestamp,
    TIMESTAMP '2016-10-05 02:00:00' AS end_timestamp
   UNION ALL
   SELECT
    TIMESTAMP '2016-10-05 12:00:00' AS start_timestamp,
    TIMESTAMP '2016-10-05 14:00:00' AS end_timestamp
   UNION ALL
   SELECT
    TIMESTAMP '2016-10-05 23:59:00' AS start_timestamp,
    TIMESTAMP '2016-10-06 01:59:00' AS end_timestamp);

+--------------------------------------------------------------------------+
| timestamp_array                                                          |
+--------------------------------------------------------------------------+
| [2016-10-05 00:00:00+00, 2016-10-05 01:00:00+00, 2016-10-05 02:00:00+00] |
| [2016-10-05 12:00:00+00, 2016-10-05 13:00:00+00, 2016-10-05 14:00:00+00] |
| [2016-10-05 23:59:00+00, 2016-10-06 00:59:00+00, 2016-10-06 01:59:00+00] |
+--------------------------------------------------------------------------+