Start profiling a table’s data with null counts, distinct values, lengths, and generated checks that expose misleading column definitions.
Trivial Plan: Why Some Queries Skip Full Optimization
Identify a trivial plan in SSMS and cached XML, understand skipped optimizer work, and compare a more complex query without forcing it.
What is Faster, SUM or COUNT? – Interview Question of the Week #231
Question: What is Faster, SUM or COUNT? Answer: Both are the same. I was asked this question during my Comprehensive Database Performance Health Check.
SQL SERVER – Automatic Seeding of Availability Database ‘SQLAGDB’ in Availability Group ‘AG’ Failed With a Transient Error. The Operation Will be Retried
Earlier I have written few blogs about automatic seeding feature. In this blog we would learn how to fix error: Automatic seeding of availability database.
Availability Group Restore Error When You Add a Database
The availability group restore error appears when automatic seeding and a manual restore both fill the same secondary. The post explains the cause, shows read-only checks for the seeding mode and the replica roles, and gives the fix with its undo.
COPY_ONLY Full Backup Size: What Differs Between Always On Replicas
A COPY_ONLY full backup of the same database can have a different size on the primary and the secondary replica of an Always On group. This post reads the log pages in the backup messages, shows them on a standalone database and explains how to compare backups fairly. It also covers what a restore needs.
PAGELATCH_UP Waits and Suspended Sessions: Find the Hot Page
PAGELATCH_UP waits mean that sessions queue for the same page in memory, and that page can be named. This post reads the waiting sessions, turns the resource into a database, a file and a page, and tells an allocation page from an ordinary one. It then lists the fixes for tempdb and for a user database.