Tag: Query Optimizer

Early in 2019, when SQL Server 2019 was a community preview and the release was many many months away, we were delighted to see the performance benefits of batch mode processing for some row data queries (that is, no columnstore index). Now that SQL Server 2019 is being installed in production facilities, and batch mode […]

It’s a commonly held misconception, even among some knowledgeable SQL folks, that the SQL Server query optimizer evaluates different ways of executing a query and goes with the query plan that yields the lowest estimated cost. As is often the case with misconceptions, this one is not so much wrong as a bit oversimplified. The […]