OPTIMIZE FOR and RECOMPILE address parameter-sensitive plans differently; compare stable representative values with per-run compilation cost.
SQL SERVER – Identifying Statistics Used by Query
Can you find the statistics used by query? There is no direct tool or DMV for it, but I explain an indirect way through the indexes a query uses.
Row Goals: Why TOP and EXISTS Change the Plan
Inspect row goals from TOP and EXISTS, read EstimateRowsWithoutRowGoal, and compare a targeted optimizer hint using actual plans.
SQL SERVER – Outer Join Not Allowed in Indexed Views
Why is OUTER JOIN not allowed in indexed views? A reader was confused by the white paper answer, so I explain it with an example and ask for yours.
A Monthly Health Check You Can Run in Ten Minutes
Run a SQL Server health check that reviews backups, integrity-check evidence, file growth, users, build level, and space without guessing health.
SQL SERVER – Data Pages in Buffer Pool – Data Stored in Memory Cache
What is in your memory cache? A query on sys.dm_os_buffer_descriptors shows the data pages in buffer pool for each table and index.
SQL SERVER – Difference Between DATETIME and DATETIME2
A developer filled a DATETIME and a DATETIME2 column with the same value and got different results. Here is the difference between DATETIME and DATETIME2.