Metadata contention in TempDB happens when many sessions create and drop temporary tables at the same moment. This post reads the waits that point to it, explains why RESOURCE_SEMAPHORE is a different problem, and shows how SQL Server 2019 and later can keep that metadata in memory.
Why FLOAT Math Does Not Add Up in T-SQL Queries
See why FLOAT math produces approximate sums and comparisons in SQL Server, then use DECIMAL or tolerance checks for the right data.
Visible Offline Schedulers: Find CPUs SQL Server Ignores
Visible offline schedulers are CPUs that Windows shows and SQL Server refuses to use. This post reads the scheduler status with tested queries, compares it with the CPU count and affinity, and explains the two common causes. It also shows the statement that returns the CPUs to automatic affinity.
Nonclustered Primary Key Test: Last Page Insert Waits
A nonclustered primary key test shows whether a heap fixes last page insert waits. On SQL Server 2025 it doesn’t, because the key index still rises. A lane layout that spreads the inserts removes the latch wait, and the post shows the cost of that layout.
Where to Download SQL Server 2019 for FREE? – Interview Question of the Week #276
Question: Where to Download SQL Server 2019 for FREE?
Answer: This is one of the most popular questions, I keep on receiving from blog readers.
Windows Path Variable: Run oStress From Any Folder
The Windows Path variable is a list of folders that Windows searches when you type a program name. This post shows how to test a change in one window, add a folder for good and check that it works. It uses oStress and sqlcmd as the examples and ends with rules for a clean Path.
Entity-Attribute-Value Tables: Why They Hurt Queries
Understand entity-attribute-value query costs, lost types, indexing limits, and alternatives using real columns, sparse columns, or JSON.
Stress Testing with oStress – SQL in Sixty Seconds #087
One of the things which we cover in my Comprehensive Database Performance Health Check is how to do Load Testing or Stress Testing with oStress.
OPTIMIZE_FOR_SEQUENTIAL_KEY: Test the Last Page Insert Fix
OPTIMIZE_FOR_SEQUENTIAL_KEY is an index option that targets last page insert contention. This post tests it with 32 connections that insert into a clustered identity key, with the option off and on. The option changes the kind of waiting, and the post shows how to decide whether it helps your table.
SQL SERVER – Last Page Insert PAGELATCH_EX Contention Due to Identity Column
Today’s goal is to understand what is the Last Page Insert PAGELATCH_EX Contention Due to Primary Key. Let us start understanding it together.