How Can I Efficiently Paginate Large Datasets in SQL Server While Maintaining Performance?

Optimizing Pagination in SQL Server for Large Datasets

Efficiently presenting large datasets to users requires pagination – showing only a portion of results per page. However, implementing pagination without impacting performance is crucial, especially when needing a total result count beforehand.

Older SQL Server Versions (2000-2008): Row Numbering

Before SQL Server 2012, row numbering was the standard pagination technique. This involved assigning a row number using ROW_NUMBER() and filtering based on page size and number. While functional, this approach proved inefficient with substantial datasets.

SQL Server 2012 and Beyond: OFFSET and FETCH

SQL Server 2012 introduced the superior OFFSET and FETCH clauses. These directly skip a specified number of rows and retrieve only the required subset. This significantly boosts performance for large datasets by eliminating the overhead of row numbering.

Illustrative Query

The following query demonstrates retrieving the initial 10 rows and the total row count using OFFSET and FETCH in SQL Server 2012 and later:

<code class="language-sql">DECLARE @RowsPerPage INT = 10;

WITH TotalResults AS (
  SELECT COUNT(*) OVER() AS TotalRows
  FROM TableName
)
SELECT *
FROM TableName
ORDER BY id
OFFSET 0 ROWS
FETCH NEXT @RowsPerPage ROWS ONLY;

SELECT TotalRows
FROM TotalResults;</code>

Important Notes:

• An ORDER BY clause is mandatory when using OFFSET and FETCH.
• OFFSET must accompany FETCH; they cannot be used with TOP.
• Employing OFFSET and FETCH dramatically enhances performance, particularly with extensive datasets.

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