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sql - 递归 CTE 以获得顶级结果

问题描述

这是我当前的数据集。

| BIMUnique | Description                                | Quantity | SuperiorUnique | LineCode |
|-----------|--------------------------------------------|----------|----------------|-----------|
| 660084    | Top Level Order Description                | 1        | 0              | 01        |
| 660085    | Second Level Order Description             | 50       | 660084         | 01        |
| 660086    | Second Level Order Description w/sub order | 200      | 660084         | 02        |
| 660087    | Third Level Order Description              | 10       | 660086         | 07        |

我想得到这样的东西

| Top Level Description       | Immediate Parent                           | Item Description                           | Navigation (LineCode Concatenation) | Qty |
|-----------------------------|--------------------------------------------|--------------------------------------------|-------------------------------------|-----|
| Top Level Order Description | 0                                          | Top Level Order Description                | 01                                  | 1   |
| Top Level Order Description | Top Level Order Description                | Second Level Order Description             | 01.01                               | 50  |
| Top Level Order Description | Top Level Order Description                | Second Level Order Description w/sub order | 01.02                               | 200 |
| Top Level Order Description | Second Level Order Description w/sub order | Third Level Order Description              | 01.02.07                            | 10  |

我当前的 CTE 有两个问题 - 首先它不显示顶级父级，只显示直接。其次，ROW_NUMBER 只计算行数，不反映 LineCode。如果我的最终用户创建了 3 个列表项，然后删除了第 2 项，则系统不会返回并重新排序行号。

WITH bi AS 
    (
        SELECT  
          m.*, 
          CAST(ROW_NUMBER() OVER (ORDER BY m.LineCode) AS VARCHAR(MAX)) COLLATE Latin1_General_BIN AS Tree
        FROM BidItems m with (nolock)
        WHERE m.SuperiorUnique = 0 AND m.JobUnique = '12591'

        UNION ALL

        SELECT  
          m.*,  
          bi.Tree + '.' + CAST(ROW_NUMBER() OVER (PARTITION BY m.SuperiorUnique ORDER BY m.LineCode) AS VARCHAR(MAX)) COLLATE Latin1_General_BIN
        FROM BidItems m with (nolock)
        JOIN bi ON m.SuperiorUnique = bi.BIMUnique
        WHERE m.JobUnique = '12591'
    )

SELECT 
  Job.Number,
  Job.Description,
  bi.Tree,
  bi.LineCode,
  bi.Description,
  bi.Quantity,
  bi.TotalCosts,
  bi.*
FROM Job AS job with (nolock)
INNER JOIN bi ON bi.JobUnique = Job.JOBUnique
INNER JOIN BidItems AS sup with (nolock) ON bi.SuperiorUnique = sup.BIMUnique
LEFT JOIN BidItemDetail AS bid with (nolock) ON bid.BidItemUnique = bi.BIMUnique

ORDER BY Bi.Tree

我们在 MSSQL 2012

更新： LineOrder 应该是 LineCode。

标签： sqlsql-servertsqlsql-server-2012hierarchical-query

解决方案

考虑以下查询，它从根到叶子遍历树。我真的不认为需要row_number()生成路径，这显然是由LineNumbers 组成的。

with cte (TopLevelDescription, ImmediateParent, ItemDescription, Navigation, Qty, BIMUnique)
as (
    select 
        Description, 
        cast(0 as varchar(60)), 
        Description, 
        cast(LineOrder as varchar(max)), 
        Qty, 
        BIMUnique 
    from BidItems
    where SuperiorUnique = 0
    union all
    select 
        c.TopLevelDescription, 
        c.ItemDescription, 
        b.Description, 
        c.Navigation + '.' + b.LineOrder, 
        b.Qty, 
        b.BIMUnique
    from cte c
    inner join BidItems b on b.SuperiorUnique = c.BIMUnique
)
select * from cte

SQL Server 2012 上的演示：

顶层描述 | 直属父母 | 物品描述 | 导航 | 数量 | BIM独特
:---------------------------- | :-------------------------------------------------------- | :-------------------------------------------------------- | :--------- | --: | --------:
顶级订单说明 | 0 | 顶级订单说明 | 1 | 1 | 660084
顶级订单说明 | 顶级订单说明 | 二级订单说明 | 1.1 | 50 | 660085
顶级订单说明 | 顶级订单说明 | 二级订单描述 w/sub order | 1.2 | 200 | 660086
顶级订单说明 | 二级订单描述 w/sub order | 三级订单说明 | 1.2.7 | 10 | 660087

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