带有 Group By 子句的 SQL 逗号分隔行

Posted 2023-02-16

【中文标题】带有 Group By 子句的 SQL 逗号分隔行

【英文标题】：SQL comma-separated row with Group By clause

【发布时间】：2011-11-18 21:49:11

【问题描述】：

我有以下疑问：

SELECT
  Account,
  Unit,
  SUM(state_fee),
  Code
FROM tblMta
WHERE MTA.Id = '123'
GROUP BY Account,Unit

这当然会引发异常，因为代码不在group by 子句中。每个 state_fee 都有一个代码。如何让此代码显示在 1 条记录中（每个 state_fee 1 个代码，每个单元有多个 state_fee）作为逗号分隔的列表？我在这里查看了不同的解决方案，但找不到任何与 group by 一起使用的解决方案。

【参考方案1】：

你想使用FOR XML PATH 构造：

SELECT ACCOUNT, 
       unit, 
       SUM(state_fee), 
       Stuff((SELECT ', ' + code 
              FROM   tblmta t2 
              WHERE  t2.ACCOUNT = t1.ACCOUNT 
                     AND t2.unit = t1.unit 
                     AND t2.id = '123' 
              FOR XML PATH('')), 1, 2, '') [Codes] 
FROM   tblmta t1 
WHERE  t1.id = '123' 
GROUP  BY ACCOUNT, 
          unit 

在此处查看其他示例：

SQL same unit between two tables needs order numbers in 1 cell SQL Query to get aggregated result in comma seperators along with group by column in SQL Server

【参考方案2】：

没有用于连接的内置聚合函数，但本文讨论了几种替代解决方案，包括用户定义的连接聚合函数：

https://www.simple-talk.com/sql/t-sql-programming/concatenating-row-values-in-transact-sql/

【讨论】：

一开始我以为projectdms只是刮掉了没有署名的原始文章，但实际上该站点属于文章作者

链接已失效。这是另一种选择：simple-talk.com/sql/t-sql-programming/…

【参考方案3】：

这将显示表、索引名称、索引类型、索引列和包含的列：

with [indexes] (table_name, index_name, column_name, index_id, key_ordinal, object_id, type_desc)
as(
SELECT  distinct
  T.[name] AS [table_name], I.[name] AS [index_name], 
  AC.[name] AS [column_name],
  I.[index_id], IC.[key_ordinal], T.[object_id], i.type_desc
FROM sys.[tables] AS T  
  INNER JOIN sys.[indexes] I ON T.[object_id] = I.[object_id]  
  INNER JOIN sys.[index_columns] IC ON I.[object_id] = IC.[object_id]  and IC.index_id=I.index_id
  LEFT OUTER JOIN sys.[all_columns] AC ON T.[object_id] = AC.[object_id] AND IC.[column_id] = AC.[column_id] 
WHERE T.[is_ms_shipped] = 0 AND I.[type_desc] <> 'HEAP'
)
select
    distinct
    db_name() as dbname,
    type_desc,
    table_name,
    index_name,
    column_name,
    STUFF((
        select ', ' + column_name
        from [indexes] t2
        where t1.table_name=t2.table_name and t1.[index_name]=t2.[index_name] and t2.[key_ordinal] = 0
        for xml path('')), 1, 2, '') inc_cols
from [indexes] t1
where t1.[key_ordinal] = 1
GROUP BY table_name, index_name, type_desc, column_name