Question

所以我的任务是创建一个SQL Server存储过程来组装员工的地理层次结构。

该系统有3种类型的地理位置：

国家地理（根）
区域地理（1级）
地域地理（第2级）

在数据库中，地理位置表看起来与此类似：

GeographyID | GeographyType | GeographyName | ParentGeographyID |
-----------------------------------------------------------------
1             National        Nation          NULL
2             Region          South           1
3             Territory       Florida         2

还有员工表。可以将单个员工分配到上述任何地区。

例如，如果员工105被分配到＆＃34; South＆＃34;区域在XREF表中有一个条目，如下所示：

EmployeeID | GeographyID
------------------------
105           2

我需要做的是给一个员工ID，建立他们的地理层次结构。因此，员工105的结果看起来像这样：

EmployeeID | TerritoryGeographyID | RegionGeographyID | NationalGeographyID
---------------------------------------------------------------------------
105          NULL                    2                    1

我不知道如何设置这样的数据结构。我希望有人可以对这个问题有所了解。

Answer 1

鉴于预期结果应该显示所有级别，并且级别很少，有解决方案不使用递归CTE，例如

WITH G AS (
  SELECT g.GeographyID 
       , t.GeographyID TerritoryGeographyID
       , r.GeographyID RegionGeographyID
       , n.GeographyID NationalGeographyID
  FROM   Geography g
         LEFT JOIN Geography T ON (g.GeographyID = T.GeographyID)
                              AND (T.GeographyType = 'Territory')
         LEFT JOIN Geography R ON ((g.GeographyID = R.GeographyID) 
                                OR (R.GeographyID = T.ParentGeographyID))
                              AND (R.GeographyType = 'Region')
         LEFT JOIN Geography N ON ((g.GeographyID = N.GeographyID) 
                                OR (N.GeographyID = R.ParentGeographyID))
                              AND (N.GeographyType = 'National')
)
SELECT E.EmployeeID
     , TerritoryGeographyID
     , RegionGeographyID
     , NationalGeographyID
FROM   Employee E
       INNER JOIN G ON E.GeographyID = G.GeographyID;

在CTE Geography被分区并从垂直方向重新组合，主要查询JOIN“PIVOT ed”数据到员工数据，ID可以将[trn].GeographyID更改为[trn].GeographyName

，将其更改为位置名称

可以显示分区，为每个级别定义CTE

With N AS (
  SELECT GeographyID, GeographyName
  FROM   Geography
  WHERE  GeographyType = 'National'
), R AS (
  SELECT GeographyID, GeographyName, ParentGeographyID
  FROM   Geography
  WHERE  GeographyType = 'Region'
), T AS (
  SELECT GeographyID, GeographyName, ParentGeographyID
  FROM   Geography
  WHERE  GeographyType = 'Territory'
), G AS (
  SELECT g.GeographyID 
       , t.GeographyID TerritoryGeographyID
       , r.GeographyID RegionGeographyID
       , n.GeographyID NationalGeographyID
  FROM   Geography g
         LEFT JOIN Geography T ON (g.GeographyID = T.GeographyID)
         LEFT JOIN Geography R ON (g.GeographyID = R.GeographyID)
                               OR (R.GeographyID = T.ParentGeographyID)
         LEFT JOIN Geography N ON (g.GeographyID = N.GeographyID) 
                               OR (N.GeographyID = R.ParentGeographyID)
)
SELECT E.EmployeeID
     , TerritoryGeographyID
     , RegionGeographyID
     , NationalGeographyID
FROM   Employee E
       INNER JOIN G ON E.GeographyID = G.GeographyID;

SQLFiddle demo

在SQL Server中创建数据层次结构

1 个答案: