Is There a Faster Alternative to Standard DELETE Statements for Bulk Deletion in SQL Server 2008?

Efficient Bulk DELETE in SQL Server 2008

In database management, the need for efficient data deletion arises frequently. While SQL Server provides standard DELETE statements, they can be time-consuming for large datasets. This question explores whether SQL Server offers an alternative to Bulk Copy (bcp) for bulk DELETE operations.

Can't Use TRUNCATE, Use WHERE Instead

The presented query asks if there's a solution for bulk DELETE in SQL Server. The catch is that the deletion should be limited by a WHERE clause, making TRUNCATE an unsuitable option.

No Bulk Copy Equivalent for DELETE

Unfortunately, there is no bulk copy equivalent for DELETE operations in SQL Server. DELETE statements with WHERE clauses must be executed as standard SQL queries.

Batch DELETEs for Scalability

For large datasets, consider batch DELETE operations. These involve breaking the DELETE statement into smaller batches, as shown below:

SELECT 'Starting' --sets @@ROWCOUNT
WHILE @@ROWCOUNT <> 0
    DELETE TOP (xxx) MyTable WHERE ...

Alternate Method for High-Percentage Deletions

When deleting a vast majority of rows, an alternative method might be more efficient:

SELECT col1, col2, ... INTO #Holdingtable
           FROM MyTable WHERE ..opposite condition..
TRUNCATE TABLE MyTable
INSERT MyTable (col1, col2, ...)
           SELECT col1, col2, ... FROM #Holdingtable

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