Row mode memory grant feedback needs compatibility level 150 or higher, while batch mode needs only 140. A tested demo runs a row mode sort and a batch mode sort at levels 140, 150 and 170. The row sort keeps its grant of 11,888 KB at level 140 and drops to 1,536 KB at 150.
What is the Priority of Database Scoped Configurations? – Interview Question of the Week #254
Question: What is the Priority of Database Scoped Configurations over Global Configuration at Server Level?
Answer: This is a follow-up question.
Database Scoped Configuration Options in SQL Server
Database scoped configuration options change how one database behaves, without touching the server. This post lists all 41 options on SQL Server 2025, finds the 7 ids that are missing, and changes and restores two settings in a demo database. It also answers the old question about configuration id 5.
Missing tempdb Files: master_files vs database_files
Missing tempdb files show up as a mismatch between sys.master_files and tempdb.sys.database_files. This post compares the two with a query, simulates the missing files on a copy of the catalog, and shows the error log message that gives the cause. The fix is to correct the path and restart.
Why Query Cost Percentages in a Plan Mislead You
Test why query cost percentages are estimates by comparing two statements with STATISTICS IO, TIME, and query DMV counters.
Memory Grant Feedback Events: Capture Them in T-SQL
Memory grant feedback events list every query whose memory grant keeps changing, and the moment SQL Server gives up on it. This post creates the Extended Events session in T-SQL, watches it live in SSMS and reads it with one query that names the procedure.
Comparing a Good and a Bad Plan for One Query in Query Store
Compare a good and a bad plan in Query Store using runtime history, SSMS Compare Showplan, estimates, joins, grants, and parallelism.