SQL Server MVP Deep Dives

Chapter 8. What makes a bulk insert a minimally logged operation?

Denis Gobo

By using a minimally logged operation, SQL Server doesn’t have to work as hard as if the operation was fully logged. The result is that your import will be much faster, and also that your log file could be a fraction of the size of a fully logged operation.

Before we start, we first need to understand what a minimally logged operation is. A minimally logged operation logs only the pages and extents that are affected; a fully logged operation will log all the individual insert, update, and delete statements. If you have 100 insert statements in a fully logged operation, you’d have 100 entries in the log file, whereas if it were minimally logged, you’d only have one ...