SQL SERVER – Performance Comparison IN vs OR

Some questions never get old and some question and I believe we will be discussing them for many more years in the future. Just other days, I received this question during my SQL Server Performance Tuning Practical Workshop. The question was about Performance Comparison IN vs OR. Though personally, I have answered this question quite a many times before, let us answer it once again, it never hurts to repeat the truth multiple times.

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SELECT One by Two – Interview Question Extended – Part II

The puzzles are interesting and in most cases, if we try to play around a little bit more, many more interesting extensions can be added. A couple of weeks back, I wrote a round – SELECT One by Two – Why Does SELECT 1/2 Returns 0 – Interview Question of the Week #067. It brought some good interactions as comments over the blog and I was happy we were all excited about something as simple as this.

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SQL SERVER – 2005 Comparison EXCEPT operator vs. NOT IN

The EXCEPT operator returns all of the distinct rows from the query to the left of the EXCEPT operator when there are no matching rows in the right query. The EXCEPT operator is equivalent of the Left Anti Semi Join. EXCEPT operator works the same way NOT IN. EXCEPTS returns any distinct values from the query to the left of the EXCEPT operand that do not also return from the right query.

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