In this video, we are going to see how the SQL EXISTS and NOT EXISTS operators work and when you should use them.
Although these operators have been available since SQL:86, the very first edition of the SQL Standard, I found that there are still many application developers who don’t realize how powerful SQL subquery expressions really are when it comes to filtering a given table based on a condition evaluated on a different table.
This video is just a sample of my High-Performance SQL video course.
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