按 T​​-SQL 中的每 N 条记录分组 [英] Group by every N records in T-SQL

问题描述

我对数据库有一些性能测试结果，我想做的是每1000条记录分组(之前按日期升序排列)，然后用AVG聚合结果.

I have some performance test results on the database, and what I want to do is to group every 1000 records (previously sorted in ascending order by date) and then aggregate results with AVG.

我实际上是在寻找标准的 SQL 解决方案，但也欢迎任何特定于 T-SQL 的结果.

I'm actually looking for a standard SQL solution, however any T-SQL specific results are also appreciated.

查询如下所示:

SELECT TestId,Throughput  FROM dbo.Results ORDER BY id

推荐答案

WITH T AS (
  SELECT RANK() OVER (ORDER BY ID) Rank,
    P.Field1, P.Field2, P.Value1, ...
  FROM P
)
SELECT (Rank - 1) / 1000 GroupID, AVG(...)
FROM T
GROUP BY ((Rank - 1) / 1000)
;

这样的事情应该会让你开始.如果您能提供您的实际架构，我可以酌情更新.

Something like that should get you started. If you can provide your actual schema I can update as appropriate.

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