I handed AI a plan with no warnings and healthy numbers, yet it read five million rows to return seventeen. That is the real test of AI execution plan analysis.
Parameter Sensitive Plan optimization in SQL Server 2022 – SQL in Sixty Seconds #200
SQL Server 2022 introduces Parameter Sensitive Plan Optimization (PSPO), a feature that revolutionizes the performance of parameterized queries.
PSPO Plan Variants: One Query, Several Plans in SQL Server
PSPO plan variants let SQL Server cache up to three plans for one parameterized query when the data is very skewed. This post builds a skewed table, shows two variants with different reads for three calls, compares the same calls with the feature off, and explains when PSPO does not apply.
SQL SERVER – Parameter Sniffing and Bad Plan
Disabling parameter sniffing does not guarantee that a bad plan becomes good. That remains my answer to the customer question.
sys.dm_exec_valid_use_hints: Every USE HINT Your Server Knows
sys.dm_exec_valid_use_hints lists every USE HINT name that your SQL Server accepts. This post groups the 35 names on SQL Server 2025 and shows the compile error for a misspelled hint. It applies two hints and reads the plan to prove each one worked, then compares USE HINT with QUERYTRACEON.
Multiple OPTIMIZE FOR Hints in One Query: Value or UNKNOWN
Multiple OPTIMIZE FOR hints in one query are written as one list: each parameter gets its own value or UNKNOWN. This post compiles the same query six ways, reads the compile values and estimated rows from the plan cache, and shows which combinations SQL Server accepts.
What is Stored in TempDB? – Interview Question of the Week #271
Question: What is Stored in TempDB?
Answer: In my recent conversation my client asked me if I know what is currently stored in their TempDb.