希望为初始查询中缺少的角色生成新行

Question

我有一组当前数据，如下所示：

Table 姓名：Project_EffectiveDating

ProjectCode	RoleCode	EffectiveDate
1a1	A	1/1/2020
1a1	B	1/1/2020
1a1	C	1/1/2020
1a1	D	1/1/2020
1a1	E	1/1/2020
1a1	A	2/1/2020

ProjectCode	RoleCode	EffectiveDate
1a1	A	1/1/2020
1a1	B	1/1/2020
1a1	C	1/1/2020
1a1	D	1/1/2020
1a1	E	1/1/2020
1a1	A	2/1/2020
1a1	B	2/1/2020
1a1	C	2/1/2020
1a1	D	2/1/2020
1a1	E	2/1/2020

其中顶部 table 是现有数据，底部 table 是所需的输出。

我一直在尝试通过以下方式加入 table 本身：

select 
  dbd.projectcode
, dbd.role
, dbd.effectivedate
from Project_EffectiveDating as dbd 
left join Project_EffectiveDating as dad 
     on dad.projectcode = dbd.projectcode 
     and dbd.rolecode <> dad.rolecode

但显然这是行不通的。我正在考虑使用 WHERE NOT IN() 做联合声明但我不知所措。任何帮助将不胜感激。

Answer 1

您似乎想要 ProjectCode/RoleCode 和 EffectiveDate 对之间的笛卡尔积：

select *
from (select distinct ProjectCode, RoleCode
      from Project_EffectiveDating
     ) pr cross join
     (select distinct EffectiveDate
      from Project_EffectiveDating
     ) e;

如果要添加不存在的行：

insert into Project_EffectiveDating (ProjectCode, RoleCode, EffectiveDate)
    select pr.ProjectCode, pr.RoleCode, e.EffectiveDate
    from (select distinct ProjectCode, RoleCode
          from Project_EffectiveDating
         ) pr cross join
         (select distinct EffectiveDate
          from Project_EffectiveDating
         ) e left join
         Project_EffectiveDating ped
         on ped.ProjectCode = pr.ProjectCode and
            ped.RoleCode = pr.RoleCode and
            ped.EffectiveDate = pr.EffectiveDate
    where ped.ProjectCode is null;

希望为初始查询中缺少的角色生成新行

Looking to generate new rows for roles missing in initial query

sql

sql-server-2008