Batch Deletions in SQL Server


This script will delete rows within a table that are out-with the specified retention period. This can be useful if you’re running deletes on large tables, and particularly if;

# Deletes are taking a long time & you’re finding it difficult to track progress.
# You have a short maintenance window each day to perform such tasks, which could be due to caution over blocking/deadlocks.
# Your server is not equipped to handle the log file bloat associated with running the delete as a single transaction.

Whatever the reason is, this is a useful script to have in the toolbelt.

I’ve set this to delete 10k rows at a time, although you can find your own sweet spot.

To find out how long it’ll take until all rows have been deleted, you could;
1. Get row counts.
2. Run deletion script for 10 minutes.
3. Check how many rows were affected.
4. Refresh Disk Usage by Top Tables report / get new counts.
5. Compare numbers above.
6. If the math works out to be 9 months before it’ll finish, then get an index added.



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