Well, let us figure out the answer to this question in today’s blog post where I will be doing a performance comparison of 16 CPU vs 1 CPU.
Multiple OPTIMIZE FOR Hints in One Query: Value or UNKNOWN
Multiple OPTIMIZE FOR hints in one query are written as one list: each parameter gets its own value or UNKNOWN. This post compiles the same query six ways, reads the compile values and estimated rows from the plan cache, and shows which combinations SQL Server accepts.
SQL SERVER – DISTINCT Does Not Guarantee ORDER BY
DISTINCT removes duplicate result rows without guaranteeing their order. My original claim that it always sorts output was incorrect.
Scan Count Zero in STATISTICS IO: What the Number Means
Scan count zero in STATISTICS IO is not an error and not a free read. This post runs nine small queries and shows what 0, 1, 2 and 5 mean, why a unique lookup counts as zero, and why logical reads are the number to compare.
Arrow in Execution Plan – SQL in Sixty Seconds #136
Do you know what a single arrow means in an execution plan? While we popularly call it the arrow, there is a technical name for these little arrows.
What is EDGE in SQL Server Execution Plan? – Interview Question of the Week #298
Question: What is EDGE in SQL Server Execution Plan?
Answer: It is the arrow or the line which goes from one operator to another operator.
Performance Regression After a SQL Server Upgrade: First Aid
A performance regression after an upgrade hurts most when users are waiting. This post shows a first-aid switch that brings back the old row estimates without lowering the compatibility level, and proves with a demo what changes and what stays. It also covers the undo, the per-query options and the steps that find the real cause.