1

假设这些表：

组：（ID，标题）： {1,G1}, {2,G2}, {3,G3}, {4, G4}

类别：（ID，标题）：{1, Cat1}, {2, Cat2}, {3, Cat3}, {4, Cat4}

产品：（Id、GroupId、CategoryId、名称）：

{1, 1, 1, G1C1P1},
{2, 1, 2, G1C2P2},
{3, 1, 2, G1C2P3},
{4, 2, 2, G2C2P4},
{5, 2, 2, G2C2P5},
{6, 3, 1, G3C1P6},
{7, 3, 3, G3C3P7}

经销商：（ID，名称）： {1, 'Dealer1'}, {2, 'Dealer2'}, {3, 'Dealer3'}

ProductDealer（Id、ProductId（英国）、DealerId、LastSale、编号）：

{1, 1, 1, 5, '2012-12-10 12:34:31'}, 
{2, 2, 2, 120, '2012-11-10 12:34:31'}, 
{3, 5, 1, 75, '2012-12-02 12:34:31'}

所以我要创建一个完整的产品视图，这是我的第一次尝试：

SELECT 
    [PR].[Id],
    [PR].[Name],
    [PR].[GroupId],
    [GR].[Title] AS [Group],
    [PR].[CategoryId],
    [CA].[Title] AS [Category]

FROM [dbo].[Product] AS [PR]
INNER JOIN [dbo].[Group] AS [GR] ON [PR].[GroupId] = [GR].[Id]
INNER JOIN [dbo].[Category] AS [CA] ON [PR].[CategoryId] = [CA].[Id]

然后我想添加ProductDealer列来查看，所以我试试这个：

SELECT 
    [PR].[Id],
    [PR].[Name],
    [PR].[GroupId],
    [GR].[Title] AS [Group],
    [PR].[CategoryId],
    [CA].[Title] AS [Category],
    ISNULL(
    (SELECT [PD].[Id] FROM [dbo].[ProductDealer] AS [PD] 
     WHERE [PD].[ProductId] = [PR].[Id]),
     CAST(-1 AS BIGINT)
    ) AS [ProductDealerId],
    ISNULL(
    (SELECT [DE].[Id] FROM [dbo].[Dealer] AS [DE]
    INNER JOIN [dbo].[ProductDealer] AS [PD] ON [DE].[Id] = [PD].[DealerId]
     WHERE [PD].[ProductId] = [PR].[Id]),
     CAST(-1 AS BIGINT)
    ) AS [DealerId],
     ISNULL(
    (SELECT [DE].[Name] FROM [dbo].[Dealer] AS [DE]
    INNER JOIN [dbo].[ProductDealer] AS [PD] ON [DE].[Id] = [PD].[DealerId]
     WHERE [PD].[ProductId] = [PR].[Id]),
     CAST('HaveNotDealer' AS NVARCHAR)
    ) AS [Dealer],
    ISNULL(
    (SELECT [PD].[LastSale] FROM [dbo].[ProductDealer] AS [PD] 
     WHERE [PD].[ProductId] = [PR].[Id]),
    CAST('0001-01-01 00:00:01' AS DATETIME2)
    ) AS [LastSale],
    ISNULL(
    (SELECT [PD].[Number] FROM [dbo].[ProductDealer] AS [PD] 
     WHERE [PD].[ProductId] = [PR].[Id]),
    CAST(0 AS BIGINT)
    ) AS [SaleNumber]

FROM [dbo].[Product] AS [PR]
INNER JOIN [dbo].[Group] AS [GR] ON [PR].[GroupId] = [GR].[Id]
INNER JOIN [dbo].[Category] AS [CA] ON [PR].[CategoryId] = [CA].[Id]

正如您在我写了一个完整的选择查询中的每一列看到的那样，ProductDealer我不知道有没有更好的方法来做到这一点？类似于将此列合并到第一个视图，您对最好实施它的建议是什么？

更新

在ProductDealer表中，ProductId是英国，所以每个产品可能有一个经销商或没有经销商，如果产品有经销商，我想要ProductDealer查看列，如果没有，则获取我的默认值，例如：（-1，'HaveNotDealer'）。

4

4 回答 4

3 
SELECT 
    [PR].[Id],
    [PR].[Name],
    [PR].[GroupId],
    [GR].[Title] AS [Group],
    [PR].[CategoryId],
    [CA].[Title] AS [Category],
    ISNULL([PD].[Id],
    CAST(-1 AS BIGINT)) AS [ProductDealerId],
    ISNULL([D].Id,
    CAST(-1 AS BIGINT)) as DealerId,
    ISNULL([D].Name,
    CAST('HaveNotDealer' AS NVARCHAR)) as DealerName,
    ISNULL(PD.LastSale,
    CAST('0001-01-01 00:00:01' AS DATETIME2)) as LastSale,
    ISNULL([PD].Number,
    CAST(0 AS BIGINT)) as SaleNumber

FROM [dbo].[Product] AS [PR]
INNER JOIN [dbo].[Group] AS [GR] ON [PR].[GroupId] = [GR].[Id]
INNER JOIN [dbo].[Category] AS [CA] ON [PR].[CategoryId] = [CA].[Id]
LEFT OUTER JOIN [dbo].[ProductDealer] AS [PD] ON [PR].[Id] = [PD].[ProductId]
LEFT OUTER JOIN [dbo].[Dealer] AS [D] ON [PD].DealerId = [D].Id
于 2012-12-10T14:21:52.350 回答
1

这是“垂直联合”版本：

WITH "Group"
     AS
     (
      SELECT * 
        FROM (
              VALUES (1,'G1'), (2,'G2'), (3,'G3'), (4, 'G4')
             ) AS T (Id, Title)
     ),
     Category
     AS
     (
      SELECT * 
        FROM (
              VALUES (1, 'Cat1'), (2, 'Cat2'), (3, 'Cat3'), (4, 'Cat4')
             ) AS T (Id, Title)
     ),
     Product
     AS
     (
      SELECT * 
        FROM (
              VALUES (1, 1, 1, 'G1C1P1'),
                     (2, 1, 2, 'G1C2P2'),
                     (3, 1, 2, 'G1C2P3'),
                     (4, 2, 2, 'G2C2P4'),
                     (5, 2, 2, 'G2C2P5'),
                     (6, 3, 1, 'G3C1P6'),
                     (7, 3, 3, 'G3C3P7')
             ) AS T (Id, GroupId, CategoryId, Name)
     ),
     Dealer
     AS
     (
      SELECT * 
        FROM (
              VALUES (1, 'Dealer1'), (2, 'Dealer2'), (3, 'Dealer3')
             ) AS T (Id, Name)
     ),
     ProductDealer 
     AS
     (
      SELECT *
        FROM (
              VALUES (1, 1, 1, 5, '2012-12-10 12:34:31'), 
                     (2, 2, 2, 120, '2012-11-10 12:34:31'), 
                     (3, 5, 1, 75, '2012-12-02 12:34:31')
             ) AS T (Id, ProductId, DealerId, Number, LastSale)
     )     
SELECT PR.Id, PR.Name, PR.GroupId, GR.Title AS "Group",
       PR.CategoryId, CA.Title AS Category, 
       PD.Id AS ProductDealerId,
       D.Id DealerId,
       D.Name AS DealerName,
       PD.LastSale AS LastSale,
       PD.Number AS SaleNumber
  FROM Product AS PR
       JOIN "Group" AS GR ON PR.GroupId = GR.Id
       JOIN Category AS CA ON PR.CategoryId = CA.Id
       JOIN ProductDealer AS PD ON PR.Id = PD.ProductId
       JOIN Dealer AS D ON PD.DealerId = D.Id

UNION

SELECT PR.Id, PR.Name, PR.GroupId, GR.Title AS "Group",
       PR.CategoryId, CA.Title AS Category, 
       PD.Id AS ProductDealerId,
       CAST(-1 AS BIGINT) DealerId,
       CAST('HaveNotDealer' AS NVARCHAR) AS DealerName,
       PD.LastSale AS LastSale,
       PD.Number AS SaleNumber
  FROM Product AS PR
       JOIN "Group" AS GR ON PR.GroupId = GR.Id
       JOIN Category AS CA ON PR.CategoryId = CA.Id
       JOIN ProductDealer AS PD ON PR.Id = PD.ProductId
 WHERE PD.DealerId NOT IN ( SELECT Id FROM Dealer )

UNION

SELECT PR.Id, PR.Name, PR.GroupId, GR.Title AS "Group",
       PR.CategoryId, CA.Title AS Category, 
       CAST(-1 AS BIGINT) AS ProductDealerId,
       CAST(-1 AS BIGINT) DealerId,
       CAST('HaveNotDealer' AS NVARCHAR) AS DealerName,
       CAST('0001-01-01 00:00:01' AS DATETIME2) AS LastSale,
       CAST(0 AS BIGINT) AS SaleNumber
  FROM Product AS PR
       JOIN "Group" AS GR ON PR.GroupId = GR.Id
       JOIN Category AS CA ON PR.CategoryId = CA.Id
 WHERE PR.Id NOT IN ( SELECT ProductId FROM ProductDealer );
于 2012-12-11T10:36:38.430 回答
1

也许只是在“精神”中回答这个问题，但这是我偶然发现这个问题时正在寻找的“垂直联合列”答案=）

with aa(col1, col2) as (
    select * from (values (1,2) ) blah
),
 bb(col3, col4) as (
    select * from (values (5,6) ) blah
)

select select aa.col1, aa.col2, bb.col3, bb.col4
from aa , bb

给

col1|col2|col3|col4
1   |2   |5   |6

免责声明以上仅适用于单行aa，bb.

于 2020-05-05T18:56:20.193 回答
0

像这样：

SELECT 
    [PR].[Id],
    [PR].[Name],
    [PR].[GroupId],
    [GR].[Title] AS [Group],
    [PR].[CategoryId],
    [CA].[Title] AS [Category],
    PD.ID AS ProductDealerID,
    PD.DealerId,
    DE.Name AS Dealer,
    PD.LastSale,
    PD.Number AS SaleNumber

FROM [dbo].[Product] AS [PR]
INNER JOIN [dbo].[Group] AS [GR] ON [PR].[GroupId] = [GR].[Id]
INNER JOIN [dbo].[Category] AS [CA] ON [PR].[CategoryId] = [CA].[Id]
LEFT JOIN  ProductDealer AS [PD] ON PD.ProductId = PR.ID
LEFT JOIN  Dealer AS DE ON DE.ID = PD.DealerId
于 2012-12-10T14:26:39.040 回答