A query slowed to over 10 minutes because of a big key lookup. Here is how I optimize key lookup operations by creating an index with include columns.
Multi-Column Index Key Order: Which Column Goes First
Test index key order with equality, range, and OR predicates, then use seek predicates and logical reads to choose the lead column.
Does Sort Order in Index Column Matters for Performance? – Interview Question of the Week #199
Does the sort order in an index column matter for performance? Yes, in some specific scenarios, and here is an example from a recent Health Check question.
What is Read Ahead Read in SQL Server? – Interview Question of the Week #197
Question: What is Read Ahead Read in SQL Server?
Answer: This is SQL Server’s feature which brings data pages into the buffer cache.
Asynchronous Statistics Updates: When They Help and When They Hurt
Evaluate asynchronous statistics updates against compile latency, data-change timing, and low-priority metadata locking in SQL Server.
Inline Table-Valued Functions: Parameterized Views That Stay Fast
Compare inline table-valued functions with scalar functions, preserve customer results, and inspect plans before claiming performance gains.
SQL SERVER – Execution Plan Ignores Tabs, Spaces and Comments
Many teams skip comments in stored procedures, fearing bigger execution plans. My demo shows SQL Server ignores tabs, spaces and comments when it builds a plan.