CTE's only valid for a single operation? Are there alternatives?

I'm have been performing a MERGE operation to push data from a production database into a reporting database on a daily basis (05:00AM) but this process has recently started taking well over an hour.  I posted here the other day about this and the response was that I should consider performing a delete and corresponding append rather than using the MERGE with If Found and If not Found operation.

I wrote an SP which looks something like the following (where "FieldList" is actually a list of fields).

;WITH Recent_Production (FieldList)
AS 
(
SELECT FieldList
FROM ProductionTable
)

DELETE FROM tbl_Reports
WHERE Exists (SELECT 1 FROM Recent_Production  
WHERE Entity_ID = tbl_Reports.Entity_ID AND ProductionDate = tbl_Reports.docDate)

INSERT INTO tbl_Reports
SELECT * FROM Recent_Production

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But this does not work, because the CTE is not found in the second operation (INSERT command).  I've never used CTE's before, but I was under the impression that one of the reasons for using CTEs was to eliminate the need to define a recordset more than once in a procedure.   I've recently discovered that the CTE is only valid for the first operation after it is defined, which is why it works for either the DELETE or the INSERT, when I remark out the other one, but does not work as indicated above.

I've modified my SP to use a temp table rather than the CTE, and everything is working fine now.

Is there another option for dong this?
LVL 50
Dale FyeAsked:
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Jim HornMicrosoft SQL Server Developer, Architect, and AuthorCommented:
>CTE's only valid for a single operation?
Correct.

>Are there alternatives?
Yes.  You can define a temporary table such as #rp which will remain in scope throughout the procedure, meaning it can be used in multiple statements.
IF OBJECT_ID('tempdb..#rp') IS NOT NULL
	DROP TABLE rp

CREATE TABLE #rp (FieldList varchar(100))

INSERT INTO #rp (FieldList) 
SELECT FieldList
FROM ProductionTable

-- Not entirely sure what you're doing here so I'll not edit this beyond #rp
DELETE FROM tbl_Reports
WHERE Exists (SELECT 1 FROM #rp) 
WHERE Entity_ID = #rp.Entity_ID AND ProductionDate = tbl_Reports.docDate)

INSERT INTO tbl_Reports (ReportList) 
SELECT * FROM #rp

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Dale FyeAuthor Commented:
Thanks for the confirmation, Jim.

Dale
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