查找表中不存在的值

Question

我有7种不同的组件，从APC，BPC，CPC，DPC，FPC，LPC，MPC开始，它们连接到ParentPart。在某些情况下，有三个组件（两种）连接到父组件，其他5组件等。从下面给出的表格中，我想找出父组件中的组件以及父组件中没有的组件。

表的代码（以帮助用户，以便他们可以轻松地将它放在小提琴或某处：

CREATE TABLE #test(
PARENTPART varchar(20),
ParentDescription varchar(15),
Component varchar(15),
Altkey varchar(20),
Qty int,
)

INSERT INTO #test
VALUES ('APF.20.015.09','Person Comp','APC2032','000123',1),
('APF.20.015.09','Person Comp','APC2038','000223',1),
('APF.20.015.09','Person Comp','CPC3042','000103',1),
('APF.20.015.09','Person Comp','DPC4032','000124',1),
('APF.20.019.09','Laptop','LPC2039','000123',1),
('APF.20.019.09','Laptop','FPC2034','0001L3',1),
('APF.20.019.09','Laptop','FPC1092','0001K3',1),
('APF.20.019.09','Laptop','CPCL032','0001M3',1);

--Below is the table generated from the above code.

PARENTPART   |  ParentDescr|  Component| AltKey   |Qty|
APF.20.015.09|  Person Comp|    APC2032|    000123| 1 |
APF.20.015.09|  Person Comp|    APC2038|    000223| 1 |
APF.20.015.09|  Person Comp|    CPC3042|    000103| 1 |
APF.20.015.09|  Person Comp|    DPC4032|    000124| 1 |
APF.20.019.09|  Laptop     |    LPC2039|    000123| 1 |
APF.20.019.09|  Laptop     |    FPC2034|    0001L3| 1 |
APF.20.019.09|  Laptop     |    FPC1092|    0001K3| 1 |
APF.20.019.09|  Laptop     |    CPCL032|    0001M3| 1 |

我在上面的表中尝试了以下查询，但它只给出了有关当前组件的结果。

SELECT *,(CASE WHEN Component LIKE 'APC%' OR Component LIKE 'BPC%' OR Component LIKE 'CPC%' OR Component LIKE 'DPC%' OR Component LIKE 'FPC%'
OR Component LIKE 'LPC%' OR Component LIKE 'MPC%' THEN 'PRESENT' ELSE NULL END) as C FROM #test;

我想要以下输出：

PARENTPART   |  ParentDescr|  Component| AltKey   |Qty  |
APF.20.015.09|  Person Comp|    APC2032|    000123| 1   |
APF.20.015.09|  Person Comp|    APC2038|    000223| 1   |
APF.20.015.09|  Person Comp|    CPC3042|    000103| 1   |
APF.20.015.09|  Person Comp|    DPC4032|    000124| 1   |
APF.20.015.09|  Person Comp|    BPC    |    NULL  | NULL|
APF.20.015.09|  Person Comp|    FPC    |    NULL  | NULL|
APF.20.015.09|  Person Comp|    MPC    |    NULL  | NULL|
APF.20.015.09|  Person Comp|    LPC    |    NULL  | NULL|
APF.20.019.09|  Laptop     |    LPC2039|    000123| 1   |
APF.20.019.09|  Laptop     |    FPC2034|    0001L3| 1   | 
APF.20.019.09|  Laptop     |    FPC1092|    0001K3| 1   |
APF.20.019.09|  Laptop     |    CPCL032|    0001M3| 1   |
APF.20.019.09|  Laptop     |    APC    |    NULL  | NULL|
APF.20.019.09|  Laptop     |    BPC    |    NULL  | NULL|
APF.20.019.09|  Laptop     |    DPC    |    NULL  | NULL|
APF.20.019.09|  Laptop     |    MPC    |    NULL  | NULL|

Answer 1

使用cross join生成行 - 一个用于父项，一个用于部分。然后使用left join引入数据：

select p.parentpart, p.parentdescription,
       c.component, t.altkey, t.qty
from (select distinct parentpart, parentdescription
      from #test
     ) p cross join
     (select distinct component
      from #test
     ) c left join
     #test t
     on t.parentpart = p.parentpart and t.component = c.component;

Here是一个db <>小提琴。

这是一个返回缩写组件名称的版本：

select p.parentpart, p.parentdescription,
       coalesce(t.component, c.component_3) as component,
       t.altkey, t.qty
from (select distinct parentpart, parentdescription
      from test
     ) p cross join
     (select v.component_3
      from (values ('APC'), ('BPC'), ('CPC'), ('DPC'), ('FPC'), ('LPC'), ('MPC')) v(component_3)
     ) c left join
     test t
     on t.parentpart = p.parentpart and left(t.component, 3) = c.component_3
order by parentpart, parentdescription, component;

和相应的db<>fiddle。

Answer 2

有趣的问题。我用'表变量'：

declare @table table
(ParentPart varchar(50),
 ParentDescr varchar(30),
 Component varchar(10))

insert into @table values ('APF.20.015.09','Person Comp','APC')
insert into @table values ('APF.20.015.09','Person Comp','BPC')
insert into @table values ('APF.20.015.09','Person Comp','CPC')
insert into @table values ('APF.20.015.09','Person Comp','DPC')
insert into @table values ('APF.20.015.09','Person Comp','FPC')
insert into @table values ('APF.20.015.09','Person Comp','LPC')
insert into @table values ('APF.20.015.09','Person Comp','MPC')
insert into @table values ('APF.20.019.09','laptop','APC')
insert into @table values ('APF.20.019.09','laptop','BPC')
insert into @table values ('APF.20.019.09','laptop','CPC')
insert into @table values ('APF.20.019.09','laptop','DPC')
insert into @table values ('APF.20.019.09','laptop','FPC')
insert into @table values ('APF.20.019.09','laptop','LPC')
insert into @table values ('APF.20.019.09','laptop','MPC')

SELECT 
T2.PARENTPART,T2.ParentDescr,
CASE WHEN SUBSTRING(T1.Component,1,3) = t2.Component THEN T1.Component
ELSE T2.Component
END AS COMPONENT, T1.Altkey,T1.Qty
FROM #TEST T1
RIGHT JOIN @table T2
ON T1.PARENTPART = T2.ParentPart
AND T1.ParentDescription = T2.ParentDescr
AND SUBSTRING(T1.Component,1,3) = t2.Component

根据需要使用'order by'。