Question

我的查询：

SELECT *,
    contacts.createdAt AS contactcreatedAt,
    contacts.updatedAt AS contactupdatedAt,
    bidresponses.itemid AS bidresponseitemid,
    bidresponses.personid AS bidresponsepersonid,
    SUM(tagsitems.quantity) AS totalquantity
FROM items
LEFT OUTER JOIN tagsitems ON items.id = tagsitems.itemid
LEFT OUTER JOIN itemscontacts ON items.id = itemscontacts.itemid
LEFT OUTER JOIN contacts ON itemscontacts.contactid = contacts.id
LEFT OUTER JOIN bidresponses ON items.id = bidresponses.itemid AND itemscontacts.personid = bidresponses.personid
LEFT OUTER JOIN bidtemplatefields ON bidresponses.bidtemplatefieldid = bidtemplatefields.id
WHERE ( (items.id = 70687 OR items.id = 70595) AND itemscontacts.relationship = 's' ) AND ( items.deletedAt IS NULL )
GROUP BY items.id, tagsitems.itemid, bidresponses.personid, bidresponses.bidtemplatefieldid
ORDER BY items.id ASC

如果没有 SUM（）和 GROUP BY 子句，此查询将返回所需的结果，减去重要的totalquantity值。

目前困扰我的任务是构建GROUP BY子句，以便它“忽略”NULL或从bidresponses中丢失值。数据结果将是一组混合的项目 - 有些项目在bidresponses表中有条目，有些则没有。

修改：我希望出现bidresponses表中具有NULL值的条目。使用当前的GROUP BY子句，它们不是。 我应该注意到，我使用分组的唯一原因是我可以获得总数量值。以下是查询输出没有 SUM（）和GROUP BY子句的示例：

+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------------------+---------------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+
| id    | itemtypeid | code | description               | cost | unittypeid | projectid | companyid | createdAt           | updatedAt           | deletedAt | unittype | tagid | itemid | quantity | itemid | contactid | personid | sentdate            | responsedate | bidtemplateid | relationship | awarddate | assigndate | id   | companyid | personid | companyidOwner | parentContactid | createdAt           | updatedAt           | firstName | lastName | company             | email               | bidtemplatefieldid | itemid | bidresponse | personid | id   | bidtemplatefield | fieldtypeid | contactcreatedAt    | contactupdatedAt    | bidresponseitemid | bidresponsepersonid |
+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------------------+---------------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+
| 70595 |          1 | NULL | HD Banners                | NULL |       NULL |         7 |         1 | 2010-05-10 17:00:11 | 2010-08-14 18:57:41 | NULL      | each     |  NULL |   NULL |     NULL |  70595 |        16 |    34789 | 2010-08-14 22:37:01 |         NULL |             1 | s            |      NULL |       NULL |   16 |      NULL |     NULL |              1 |            NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 | NULL      | NULL     | sdf                 | 23523@wokd.com      |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 |              NULL |                NULL |
| 70595 |          1 | NULL | HD Banners                | NULL |       NULL |         7 |         1 | 2010-05-10 17:00:11 | 2010-08-14 18:57:41 | NULL      | each     |  NULL |   NULL |     NULL |  70595 |        22 |    34794 | 2010-08-14 18:44:02 |         NULL |             1 | s            |      NULL |       NULL |   22 |      NULL |    34794 |              1 |            NULL | 2010-08-09 19:56:28 | 2010-08-10 13:55:03 | NULL      | NULL     | anewwwww            | hmm@hmm.com         |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-09 19:56:28 | 2010-08-10 13:55:03 |              NULL |                NULL |
| 70595 |          1 | NULL | HD Banners                | NULL |       NULL |         7 |         1 | 2010-05-10 17:00:11 | 2010-08-14 18:57:41 | NULL      | each     |  NULL |   NULL |     NULL |  70595 |        27 |    34797 | 2010-08-14 22:36:59 |         NULL |             1 | s            |      NULL |       NULL |   27 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:11:52 | NULL                | NULL      | NULL     | 3k3jdjhgj@wrwer.com | 3k3jdjhgj@wrwer.com |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:11:52 | NULL                |              NULL |                NULL |
| 70595 |          1 | NULL | HD Banners                | NULL |       NULL |         7 |         1 | 2010-05-10 17:00:11 | 2010-08-14 18:57:41 | NULL      | each     |  NULL |   NULL |     NULL |  70595 |        28 |    34798 | 2010-08-14 22:37:00 |         NULL |             1 | s            |      NULL |       NULL |   28 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:18:27 | NULL                | NULL      | NULL     | 3838474@234234.com  | 3838474@234234.com  |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:18:27 | NULL                |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |    12 |  70687 |     NULL |  70687 |        16 |    34789 | 2010-08-14 22:37:01 |         NULL |             1 | s            |      NULL |       NULL |   16 |      NULL |     NULL |              1 |            NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 | NULL      | NULL     | sdf                 | 23523@wokd.com      |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |     2 |  70687 |     NULL |  70687 |        16 |    34789 | 2010-08-14 22:37:01 |         NULL |             1 | s            |      NULL |       NULL |   16 |      NULL |     NULL |              1 |            NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 | NULL      | NULL     | sdf                 | 23523@wokd.com      |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |    12 |  70687 |     NULL |  70687 |        27 |    34797 | 2010-08-14 22:36:59 |         NULL |             1 | s            |      NULL |       NULL |   27 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:11:52 | NULL                | NULL      | NULL     | 3k3jdjhgj@wrwer.com | 3k3jdjhgj@wrwer.com |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:11:52 | NULL                |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |     2 |  70687 |     NULL |  70687 |        27 |    34797 | 2010-08-14 22:36:59 |         NULL |             1 | s            |      NULL |       NULL |   27 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:11:52 | NULL                | NULL      | NULL     | 3k3jdjhgj@wrwer.com | 3k3jdjhgj@wrwer.com |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:11:52 | NULL                |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |    12 |  70687 |     NULL |  70687 |        28 |    34798 | 2010-08-14 22:37:00 |         NULL |             1 | s            |      NULL |       NULL |   28 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:18:27 | NULL                | NULL      | NULL     | 3838474@234234.com  | 3838474@234234.com  |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:18:27 | NULL                |              NULL |                NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |     2 |  70687 |     NULL |  70687 |        28 |    34798 | 2010-08-14 22:37:00 |         NULL |             1 | s            |      NULL |       NULL |   28 |      NULL |     NULL |              1 |            NULL | 2010-08-10 19:18:27 | NULL                | NULL      | NULL     | 3838474@234234.com  | 3838474@234234.com  |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-10 19:18:27 | NULL                |              NULL |                NULL |
+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------------------+---------------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+

以下是查询输出与 SUM（）和GROUP BY子句的示例：

+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------+----------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+---------------+
| id    | itemtypeid | code | description               | cost | unittypeid | projectid | companyid | createdAt           | updatedAt           | deletedAt | unittype | tagid | itemid | quantity | itemid | contactid | personid | sentdate            | responsedate | bidtemplateid | relationship | awarddate | assigndate | id   | companyid | personid | companyidOwner | parentContactid | createdAt           | updatedAt           | firstName | lastName | company | email          | bidtemplatefieldid | itemid | bidresponse | personid | id   | bidtemplatefield | fieldtypeid | contactcreatedAt    | contactupdatedAt    | bidresponseitemid | bidresponsepersonid | totalquantity |
+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------+----------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+---------------+
| 70595 |          1 | NULL | HD Banners                | NULL |       NULL |         7 |         1 | 2010-05-10 17:00:11 | 2010-08-14 18:57:41 | NULL      | each     |  NULL |   NULL |     NULL |  70595 |        16 |    34789 | 2010-08-14 22:37:01 |         NULL |             1 | s            |      NULL |       NULL |   16 |      NULL |     NULL |              1 |            NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 | NULL      | NULL     | sdf     | 23523@wokd.com |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 |              NULL |                NULL |          NULL |
| 70687 |          1 | NULL | Editing and adding labels | NULL |       NULL |         7 |         1 | 2010-05-15 07:26:33 | 2010-08-14 18:55:48 | NULL      | each     |    12 |  70687 |     NULL |  70687 |        16 |    34789 | 2010-08-14 22:37:01 |         NULL |             1 | s            |      NULL |       NULL |   16 |      NULL |     NULL |              1 |            NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 | NULL      | NULL     | sdf     | 23523@wokd.com |               NULL |   NULL | NULL        |     NULL | NULL | NULL             |        NULL | 2010-08-05 18:40:01 | 2010-08-05 18:41:40 |              NULL |                NULL |          NULL |
+-------+------------+------+---------------------------+------+------------+-----------+-----------+---------------------+---------------------+-----------+----------+-------+--------+----------+--------+-----------+----------+---------------------+--------------+---------------+--------------+-----------+------------+------+-----------+----------+----------------+-----------------+---------------------+---------------------+-----------+----------+---------+----------------+--------------------+--------+-------------+----------+------+------------------+-------------+---------------------+---------------------+-------------------+---------------------+---------------+

Answer 1

您需要在GROUP BY子句中包含所有重要的未聚合列。现在，你不按创建的等分组。

Answer 2

如果您需要所有这些行SUM()，那么所需的GROUP BY将不是一个好的解决方案。

最佳解决方案可能是在处理/循环客户端代码/脚本中的所有行时添加数量。

或者你可以查询两次，一次使用GROUP BY和SUM()来获取每个items.id的数量，但是即使在客户端代码中的所有行进行额外的循环也可能是比查询两次更快，也可能取决于结果的大小。

SQL GROUP BY和NULL值：如何仅通过非空值对结果进行分组？

2 个答案: