Diagnose a leading wildcard LIKE scan and compare prefix search, reversed suffix keys, full-text search, and n-gram indexing.
SQL SERVER – Change Collation of Database Column – T-SQL Script
How to change collation of database column with ALTER TABLE ALTER COLUMN and COLLATE, then check it in sys.columns. A short test script shows each step.
Five DMVs Worth Memorizing
Five DMVs worth memorizing show SQL Server sessions, active requests, waits, index use, and file I/O during an incident.
The Blocked Process Report
The blocked process report shows the waiting session and blocker after a configured threshold, with Extended Events capturing the XML for review.
Comparing Two Wait Stats Snapshots to See What Changed
Compare wait stats snapshots over a chosen window, subtract cumulative counters, remove background waits, and calculate rates and average waits.
SQL SERVER – Interesting Observation – Use of Index and Execution Plan
Three AdventureWorks examples show how the Query Optimizer picks an index, what happens when you force one, and how that changes the index and execution plan.
SQL SERVER – Interesting Observation about Order of Resultset without ORDER BY
Two simple AdventureWorks queries return the same rows in a different order without ORDER BY. I explain why that order is never guaranteed.