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.
Add Columns With NULL in SQL Server: ISNULL, COALESCE or SUM
To add columns with NULL in SQL Server, first decide what an empty value means. This post sums three nullable columns with the plus operator, ISNULL, COALESCE and SUM, shows where each one differs on a row of all NULLs, and compares their CPU cost on two million rows.
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.
5 Questions Answered OUTPUT Clause – SQL in Sixty Seconds #135
I have decided to create another SQL in Sixty Seconds video discussing the OUTPUT clause. In this video, we will discuss 5 questions.
Multi Tables – 1 Drop Statement – SQL in Sixty Seconds #134
It was taking time as well as require to write them one at a time. In today’s blog post we will see how we can drop multiple tables with a 1 drop statement.
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.
SQL SERVER – 7 Questions about OUTPUT Clause Answered
These 7 Questions about OUTPUT Clause follow my INSERT and DELETE videos. I clarify destinations, triggers and performance scope below.
Remove Trigger for Delete – SQL in Sixty Seconds #133
I am involved in the Comprehensive Database Performance Health Check. Today we will discuss how we can remove triggers for the Delete statement.
Create Table From Another Table: What SELECT INTO Copies
To create table from another table in SQL Server, use SELECT INTO with WHERE 1 = 2 or TOP (0) for the structure alone. This post builds a demo table and compares it with its copy column by column. It shows the identity trap, the computed column that becomes plain, and the statements that add keys, defaults and indexes back.
How to Capture Deleted Rows Without Trigger? – Interview Question of the Week #297
Question: How to Capture Deleted Rows Without Trigger?
Answer: I was recently asked by my client during the Comprehensive Database Performance Health Check.