問題描述

我有一張桌子Person:

PersonID | FirstName | LastName
-------------------------------
1        |   John    |  Doe
2        |   Jane    |  Doe
3        |  NoSpouse | Morales
4        | Jonathan  | Brand
5        | Shiela    | Wife

還有一個 Relationship 表:

RelationshipID | PersonID | Type | RelatedPersonID
1              |    1     |  3   |     2
2              |    2     |  3   |     1
3              |    4     |  3   |     5
4              |    5     |  3   |     4

所以基本上，我想結合配偶和客戶的名字，但我想排除配偶:

So basically, I want to combine the names of the spouse and client, but I want to exclude the spouse:

預期結果:

1,  John and Jane Doe, 2
----------------------
3, NoSpouse Morales, null
-----------------------
4, Jonathan and Shiela Brand, 5

我試過了:

SELECT p.PersonID,
    Case when spouse.PersonID is not null 
        THEN p.FirstName + ' and ' + spouse.FirstName + ' ' + p.LastName
    ELSE p.FirstName + ' ' + p.LastName END as ClientName,
    spouse.PersonID as RelatedPersonID
FROM Person p
LEFT JOIN Relationship r on p.PersonID = r.PersonID
LEFT JOIN Person spouse on r.RelatedPersonID = spouse.PersonID
WHERE r.Type = 3 OR spouse.PersonID is null

但結果是:

1,  John and Jane Doe, 2
----------------------
2,  Jane and John Doe, 1
----------------------
3, NoSpouse Morales, null
-----------------------
4, Jonathan and Shiela Brand, 5
-------------------------------
5, Shiela and Jonathan Wife, 4

這是一些模擬數(shù)據(jù):

create table Person(
    PersonID int primary key,
    FirstName varchar(max),
    LastName varchar(max)
)
insert into Person values 
(1, 'John', 'Doe'), 
(2, 'Jane', 'Doe'), 
(3, 'NoSpouse', 'Morales'), 
(4, 'Jonathan', 'Brand'), 
(5,'Shiela','Wife')

create table Relationship (
    RelationshipID int,
    PersonID int references Person(PersonID),
    Type int,
    RelatedPersonID int references Person(PersonID)
)
insert into Relationship values 
(1, 1, 3, 2),
(2, 2, 3, 1),
(3, 4, 3, 5),
(4, 5, 3, 4)

SELECT p.PersonID,
    Case when spouse.PersonID is not null 
        THEN p.FirstName + ' and ' + spouse.FirstName + ' ' + p.LastName
    ELSE p.FirstName + ' ' + p.LastName END as ClientName,
    spouse.PersonID as RelatedPersonID
FROM Person p
LEFT JOIN Relationship r on p.PersonID = r.PersonID
LEFT JOIN Person spouse on r.RelatedPersonID = spouse.PersonID
WHERE r.Type = 3 OR spouse.PersonID is null

drop table Relationship
drop table Person

提前感謝您的幫助和時間.

thanks in advance for your help and time.

注意:我已經(jīng)編輯了我的模擬腳本以在結果中包含 3, NoSpouse Morales, null.此外，對于丈夫/妻子，也不需要特別的標準.列表中最先被提取的人不應包括相關配偶.

NOTE: I've edited my mock script to include 3, NoSpouse Morales, null in the results. Also, there is no particular criteria needed to which is husband/wife. Whoever was fetched first in the list should not include the related spouse.

推薦答案

如果必須包含一個而另一個排除，請嘗試添加子句

If one has to be included while the other excluded, try adding a clause

AND r.PersonID < r.RelatedPersonID 

因為 ID 不相等，這將只包括其中一個:

since the IDs will not be equal and this will include only either one:

 SELECT p.PersonID,
 Case when spouse.PersonID is not null 
    THEN p.FirstName + ' and ' + spouse.FirstName + ' ' + p.LastName
 ELSE p.FirstName + ' ' + p.LastName END as ClientName,
 spouse.PersonID as RelatedPersonID
FROM Person p
LEFT JOIN Relationship r on p.PersonID = r.PersonID
LEFT JOIN Person spouse on r.RelatedPersonID = spouse.PersonID
WHERE (r.Type = 3 AND r.PersonID < r.RelatedPersonID)  OR spouse.PersonID is null

這篇關于選擇表中的人并排除妻子但合并他們的名字的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！