How Can I Efficiently Implement Paging in SQL Server for Large Datasets?

Efficient SQL Server Paging Mechanisms

When dealing with vast record lists, it's imperative to optimize data retrieval for performance reasons. To avoid overloading your system, a practical approach is to implement paging, allowing users to select specific subsets of data.

Row Number Approach

Adding a row number to each record and filtering based on that number is a viable solution. However, it may introduce performance overhead, especially when the table is large.

Optimized Stored Procedure

The following T-SQL stored procedure provides a highly efficient paging mechanism:

CREATE  PROCEDURE dbo.PagingTest
(
    @PageNumber int,
    @PageSize int
)
AS

DECLARE @FirstId int, @FirstRow int

SET @FirstRow = ( (@PageNumber - 1) * @PageSize ) + 1
SET ROWCOUNT @FirstRow

-- Add check here to ensure that @FirstRow is not
-- greater than the number of rows in the table.

SELECT   @FirstId = [Id]
FROM     dbo.TestTable
ORDER BY [Id]

SET ROWCOUNT @PageSize

SELECT   *
FROM     dbo.TestTable
WHERE    [Id] >= @FirstId
ORDER BY [Id]

SET ROWCOUNT 0
GO

This stored procedure utilizes the SQL optimizer's ability to efficiently find the first ID. Combined with ROWCOUNT, it ensures a CPU and read-efficient approach. It is particularly effective for tables with a substantial number of rows.

Considerations

• The stored procedure relies on a sequential identity column or a suitable column for page sorting.
• If using a column with non-unique values, add a secondary sort column to ensure uniqueness.
• Prior to executing the stored procedure, consider adding a check to verify that the requested first row doesn't exceed the available rows in the table.

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