March 2023 Discount: Comprehensive Database Performance Health Check | Testimonials

SQL SERVER – Interesting Observation of ON Clause on LEFT JOIN – How ON Clause affects Resultset in LEFT JOIN

Pinal Dave
SQL, SQL Performance, SQL Puzzle, SQL Server, SQL Tips and Tricks
SQL Joins, SQL Scripts
Today I received email from Yoel from Israel. He is one smart man always bringing up interesting questions. Let us see his latest email first. Hi Pinal, I am subscribed to your blog and enjoy reading it. I have a question which has been bothering me for some time now.…
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SQL SERVER – Observation – Effect of Clustered Index over Nonclustered Index

Pinal Dave
SQL, SQL Performance, SQL Puzzle, SQL Server, SQL Tips and Tricks
SQL Constraint and Keys, SQL Index, SQL Scripts
Today I came across very interesting observation while I was working on query optimization. Let us run the example first. Make sure to to enable Execution Plan (Using CTRL + M) before running comparison queries. USE [AdventureWorks] GO /* */ CREATE TABLE [dbo].[MyTable]( [ID] [int] NOT NULL, [First] [nchar](10) NULL,…
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SQL SERVER – Interesting Interview Questions – Revisited

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Puzzle, SQL Server, SQL Tips and Tricks
Best Practices, Software Development, SQL Scripts
I really enjoyed users participation in my previous question. Read SQL SERVER – Interesting Interview Questions before continuing reading this article. This interview question was about user participation and about how good and how different you can come with your T-SQL script. What I really liked is that many users…
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SQL SERVER – Interesting Interview Questions – Part 2 – Puzzle – Solution

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Puzzle, SQL Server, SQL Tips and Tricks
Best Practices, SQL Scripts
Yesterday we looked at Puzzle and I did got great response to this question. Very interestingly not many got it right. First go through the puzzle first and then come back here and read answer. Read Original Interview Question and Puzzle. Question: Select all the person from table PersonColor who…
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