CTE, ROW_NUMBER and ROWCOUNT
I am trying to return a page of data and also row count of all data in one stored procedure which looks like following:
WITH Props AS
(
SELECT *,
ROW_NUMBER() OVER (ORDER BY PropertyID) AS RowNumber
FROM Property
WHERE PropertyType = @PropertyType AND ...
)
SELECT * FROM Props
WHERE RowNumber BETWEEN ((@PageNumber - 1) * @PageSize) + 1 AND (@PageNumber * @PageSize);
I am unable to return the row count (highest row number).
I know this has already been discussed (I've seen this:
Efficient way of getting @@开发者_运维知识库rowcount from a query using row_number) but when I add COUNT(x) OVER(PARTITION BY 1)
in the CTE, the performance degrades and the query above that normally takes no time takes forever to execute. I reckon it's because the count is calculated for each row? I seems that I can't reuse the CTE in another query. Table Props has 100k records, CTE returns 5k records.
In T-SQL it should be
;WITH Props AS
(
SELECT *,
ROW_NUMBER() OVER (ORDER BY PropertyID) AS RowNumber
FROM Property
WHERE PropertyType = @PropertyType AND ...
)
, Props2 AS
(
SELECT COUNT(*) CNT FROM Props
)
-- Now you can use even Props2.CNT
SELECT * FROM Props, Props2
WHERE RowNumber BETWEEN ((@PageNumber - 1) * @PageSize) + 1 AND (@PageNumber * @PageSize);
now you have CNT in every line... Or you wanted something different? You wanted a second resultset with only the count? Then do it!
-- This could be the second result-set of your query.
SELECT COUNT(*) CNT
FROM Property
WHERE PropertyType = @PropertyType AND ...
Note: reedited, the query 1 David was referencing now has been trashcanned, query 2 is now query 1.
You want the count for the whole resultset right?
does this work speedwise?
SELECT *,(select MAX(RowNumber) from Props) as MaxRow
FROM Props
WHERE RowNumber BETWEEN ((@PageNumber - 1) * @PageSize) + 1
AND (@PageNumber * @PageSize);
I had the same problem and wanted to share the code which would return page and total rows. The problem is fixed by a temporary table. Here is the body of the stored procedure:
DECLARE @personsPageTable TABLE(
RowNumber INT,
PersonId INT,
FirstName NVARCHAR(50),
LastName NVARCHAR(50),
BirthDate DATE,
TotalCount INT);
;WITH PersonPage AS
(
SELECT
ROW_NUMBER() OVER(ORDER BY persons.Id) RowNumber,
Id,
FirstName,
LastName,
BirthDate
FROM Persons
WHERE BirthDate >= @BirthDateFrom AND BirthDate <= @BirthDateTo
), TotalCount AS( SELECT COUNT(*) AS [Count] FROM PersonPage)
INSERT INTO @personsPageTable
SELECT *, (select * from TotalCount) TotalCount FROM PersonPage
ORDER BY PersonPage.RowNumber ASC
OFFSET ((@pageNumber - 1) * @pageSize) ROWS
FETCH NEXT @pageSize ROWS ONLY
SELECT TOP 1 TotalCount FROM @personsPageTable
SELECT
PersonId,
FirstName,
LastName,
BirthDate
FROM @personsPageTable
As you can see I put CTE result and total rows into the temporary table and select two queries. The first return total count and the second return page with data.
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