Select 查询 Sum 并将其分组

Question

我对合并项目列感到困惑。请帮我做一下。

Answer 1

您真的应该更多地了解 SQL 并阅读您的具体数据库类型的文档 - SQL 不同数据库的查询略有不同。不过在 MySQL 你可以这样做：

SELECT GROUP_CONCAT(Item SEPARATOR ' | '), SUM(Qty), SUM(ST), SUM(Amt) FROM <supplier> GROUP BY Supplier;

其中 <供应商> 应替换为您的 table。

Answer 2

PostgreSQL 中的解决方案。请注意 distinct item.

select string_agg(distinct item, '|') items, supplier, 
       sum(qty) qty, sum(st) st, sum(amt) amt
from the_table 
group by supplier;

编辑
sql-server 数据库被标记后，我上面的回答不再相关。

Answer 3

Oracle/DB2/Snowflake中的解决方案SQL:
（LISTAGG 函数符合 ANSI/SQL:2016 标准，但并非每个最新的 RDBMS 版本都普遍支持）

SELECT
 LISTAGG(Item, '|') WITHIN GROUP (ORDER BY Qty) AS Item, 
 Supplier, 
 SUM(Qty) AS Qty, 
 SUM(St) AS St, 
 SUM(Amt) AS Amt
FROM yourtable 
GROUP BY Supplier
ORDER BY Supplier

MS Sql Server 2014 的解决方案：

SELECT
 STUFF((select '|'+ t2.Item
        from yourtable t2
        where t2.Supplier = t.Supplier
        order by t2.Qty
        for xml path ('')),1,1,'') AS Item,
 Supplier, 
 SUM(Qty) AS Qty,
 SUM(St) AS St, 
 SUM(Amt) AS Amt
FROM yourtable t
GROUP BY Supplier
ORDER BY Supplier

MS Sql Server 2017+ 使用 STRING_AGG 的解决方案：

SELECT
 STRING_AGG(Item, '|') WITHIN GROUP (ORDER BY Qty) AS Item,
 Supplier, 
 SUM(Qty) AS Qty,
 SUM(St) AS St, 
 SUM(Amt) AS Amt
FROM yourtable t
GROUP BY Supplier
ORDER BY Supplier

Answer 4

您可以将此用于 SQL 服务器 < 2017

SELECT 
Supplier
,Items = STUFF((
        SELECT ' | ' + t2.Item
        FROM TestTable t2
        WHERE t.Supplier = t2.Supplier
        FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, '')
,SUM(Qty) Qty
,SUM(ST) ST
,SUM(Amt) Amt
FROM TestTable t
GROUP BY Supplier

Select 查询 Sum 并将其分组

Select Query for Sum and group it

sql

sql-server

string-aggregation

sql-server-2014