Sometimes the exact same query goes slow out of nowhere. Your current fix is to update statistics, rebuild indexes, or restart the SQL Server. It works, but you don’t know why.
The single most common reason is parameter sniffing. SQL Server “sniffs” the first set of parameters for a query, builds an execution plan for it, and then reuses that same plan no matter what parameters get called. It’s been the bane of our performance tuning for decades.
In this one-hour session on Thursday, October 20th, I will explain:
How it happens How SQL Server 2022 is trying to