如何两次引用一个CTE？ [英] How to reference one CTE twice?

问题描述

我有一个非常胖的公用表表达式，其中包含行号，以便可以返回分页的结果集。在分页结果集之前，我还想返回与查询匹配的记录总数。

I have a very fat common table expression which includes row numbers so that I can return a paged result set. I also want to return the total number of records that match the query before I page the result set.

with recs as (select *, row_number() over (order by id) as rownum from ......)
select * from recs where rownum between @a and @b .... select count(*) from recs

很显然，我上面的查询是不完整的，但这只是为了说明我的观点。我想要一个结果页面以及匹配总数。如何做到这一点而又不必照搬整个C +行的整个20粘贴？

Obviously my query above is patchy, but it's just for illustrating my point. I want a page of results AND the total number of matches. How do I do this without having to literally copy and paste the entire 20+ line CTE?

推荐答案

您可以使用逗号创建

仅说明我的意思：

with recs as (
select 
    *, 
    row_number() over (order by id) as rownum from ......
    ),
counts as (
    select count(*) as totalrows from recs
)
select recs.*,count.totalrows
from recs
cross apply counts 
where rownum between @a and @b .... 

这不是一个好的解决方案。

This is not the a good solution.

在这篇文章。

DECLARE @startRow INT; SET @startrow = 50;
WITH cols
AS
(
    SELECT table_name, column_name, 
        ROW_NUMBER() OVER(ORDER BY table_name, column_name) AS seq, 
        ROW_NUMBER() OVER(ORDER BY table_name DESC, column_name desc) AS totrows
    FROM [INFORMATION_SCHEMA].columns
)
SELECT table_name, column_name, totrows + seq -1 as TotRows
FROM cols
WHERE seq BETWEEN @startRow AND @startRow + 49
ORDERBY seq

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