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sql server - How to reference one CTE twice?

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

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?

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Don't think you can. From MSDN

A common table expression (CTE) can be thought of as a temporary result set that is defined within the execution scope of a single SELECT, INSERT, UPDATE, DELETE, or CREATE VIEW statement.

Emphasis on "single SELECT, INSERT, UPDATE, DELETE, or CREATE VIEW statement."

This might be a situation where you want to use a Temporary Table.

CREATE TABLE #Recs
{
  .....
}
INSERT INTO #Recs
select *, row_number() over (order by id) as rownum from ......

If you don't know the structure of the table before hand you can use this form to create a temporary table:

select *, row_number() over (order by id) as rownum INTO #Recs from ......

You will be able to use the Temporary table in the manner you have described above.


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