需要使用SQL Server 2008显示以下格式的数据

Question

如果我加入两个表，我将得到下表

SELECT a.Category, a.categoryid, b.parentid,b.Level
FROM a JOIN b ONa.CatId=b.Catid

实际数据：-

  Category               Catid         ParentID      Level
  -----------------------------------------------------------
  Pumps & Accss             20               0           0                                            
  Inground Pumps           213               20          1
  Above Ground             215               20          1                                              
  Commercial Pumps         216               20          1 
  Hawrd super pumps        814               213         2 
  Hywrd north pumps        815               213         2

这是一个使用游标的示例，我必须对所有类别ID都这样应用...

我需要显示以下数据：

  Cat1               Cat2           Cat3             ItemNo
  ------------------------------------------------------------
  Pumps & Accss      Above Ground   Hawrd super      AX007123 
  Pumps & Accss      Above Ground   Hywrd north      AX0071201 
  Pumps & Accss      Commercial Pu  Hawrd super      AX007754  
  Pumps & Accss      Commercial Pu  Hawrd super      AX0077891 
  Pumps & Accss      Inground Pumps Hywrd north      AX0071251

Cat1列中的Level 1和Cat2列中的Level2像这样

需要获取输出。 像这样，我有10个级别，请发布一些好的答案来解决此问题。

Answer 1

检查此...您可以在同一张表上多次使用以建立多级联接

declare @category table(categoryId int, category char(100), principalId int)
declare @article table(articleId int, article varchar(100), categoryId int)

insert into @category(categoryId, category, principalId)
values (1,'One', null)

insert into @category(categoryId, category, principalId)
values (2,'two', null)

insert into @category(categoryId, category, principalId)
values (11,'eleven', 1)

insert into @category(categoryId, category, principalId)
values (21,'twenty one', 2)

insert into @category(categoryId, category, principalId)
values (22,'twenty two', 2)

insert into @category(categoryId, category, principalId)
values (111,'one hundred eleven', 11)

insert into @category(categoryId, category, principalId)
values (211,'two hundred eleven', 21)

insert into @category(categoryId, category, principalId)
values (221,'two hundred twenty one', 22)

insert into @category(categoryId, category, principalId)
values (2211,'two thousand two hundred twenty one', 221)

insert into @article(articleId, article, categoryId)
values (1, 'Article 1', 111)

insert into @article(articleId, article, categoryId)
values (2, 'Article 2', 211)

insert into @article(articleId, article, categoryId)
values (3, 'Article 3', 221)

insert into @article(articleId, article, categoryId)
values (4, 'Article 4', 2211)

select coalesce(c5.category,'') c5,
    coalesce(c4.category,'') c4,
    coalesce(c3.category,'') c3,
    coalesce(c2.category,'') c2,
    coalesce(c1.category,'') c1,
    a.article
from @article a
    left join @category c1 on c1.categoryId = a.categoryId
    left join @category c2 on c2.categoryId = c1.principalId
    left join @category c3 on c3.categoryId = c2.principalId
    left join @category c4 on c4.categoryId = c3.principalId
    left join @category c5 on c5.categoryId = c4.principalId

如果您共享表格定义，这有助于改善我的答案，希望它可以帮助您指出正确的方向