Question

我有两个表，ActiveContacts和CompletedContacts。 ActiveContacts包含尚未关闭的联系人，但可能由CompletedContacts中的联系人产生。

我需要找到ActiveContacts中所有联系人的最小ContactStart，一直到CompletedContacts中的第一个相关联系人（如果存在）。您知道当ContactID = MasterContactID时，您已到达“根”。

例如，在我的示例数据中：

From ActiveContacts
45227565918 --> 45130250258
From CompletedContacts
45130250258 --> 45065182801
45065182801 --> 45065111275
45065111275 --> 44987017334
44987017334 --> 44986804829
44986804829 --> 44986804829 --> 2019-02-25 07:48:00.00

在某些情况下，ContactID仅存在于ActiveContact上，因为它不是从CompletedContacts上的其他联系人衍生而来的。

45562514264 --> 45562514264 --> 2019-03-27 02:44:00.000

我认为这可以通过递归CTE来实现，但我做对了。这可能吗？我唯一的另一个想法是逐行游标类型的情况。

下面的示例代码。

CREATE TABLE CustServ.WF.ActiveContactsTest
(
ContactID [bigint],
MasterContactID [bigint],
ContactStart [datetime]
);

INSERT INTO CustServ.WF.ActiveContactsTest (ContactID, MasterContactID, ContactStart)
VALUES
(45227565918,45130250258,'3/8/19 17:29'),
(45547409273,45545833249,'3/26/19 19:44'),
(45547477525,45547474793,'3/26/19 22:45'),
(45547491195,45547491195,'3/26/19 23:27'),
(45562514264,45562514264,'3/27/19 2:44');


CREATE TABLE CustServ.WF.CompletedContactsTest
(
ContactID [bigint],
MasterContactID [bigint],
ContactStart [datetime]
);

INSERT INTO CustServ.WF.CompletedContactsTest (ContactID, MasterContactID, ContactStart)
VALUES
(45130250258,45065182801,'3/4/19 17:22'),   -- From 1st row in ActiveContacts
(45065182801,45065111275,'2/28/19 14:11'),
(45065111275,44987017334,'2/28/19 13:49'),
(44987017334,44986804829,'2/25/19 9:20'),
(44986804829,44986804829,'2/25/19 7:48'),

(45545833249,45510675166,'3/26/19 9:44'),   -- From 2nd row in ActiveContacts
(45510675166,44056741709,'3/25/19 9:35'),
(44056741709,45435906188,'3/21/19 18:50'),
(45435906188,45370464489,'3/20/19 17:15'),
(45370464489,45318017172,'3/18/19 15:31'),
(45318017172,45280077660,'3/14/19 13:16'),
(45280077660,45280077660,'3/12/19 13:24'),

(45547474793,45547474793,'3/26/19 22:31');  -- From 3rd row in ActiveContacts

Answer 1

这是一个混乱的数据模型，具有在两个表中表示的链接。但是您可以这样做：

with t as (
      select contactID, MasterContactID, ContactStart, 0 as isactive
      from CompletedContactsTest
      -- where contactID = MasterContactID
      union all
      select contactID, MasterContactID, ContactStart, 1 as isactive
      from ActiveContactsTest
      -- where contactID = MasterContactID
     ),
     cte as (
      select contactID, MasterContactID, ContactStart, 1 as lev, isactive
      from t
      where contactID = MasterContactID
      union all
      select t.contactID, cte.MasterContactID, cte.ContactStart, lev + 1, t.isactive
      from t join
           cte
           on t.contactID = cte.MasterContactID
      where t.contactID <> t.MasterContactID
     )
select contactid, min(contactstart)
from cte
where isactive = 1
group by contactid;

Here是db <>小提琴。

我可以使用递归CTE在ID的“线程”中查找最小日期吗？

1 个答案: