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Databases Querying Relational Databases Set Operations What are Set Operations?

Amadou Diallo
Amadou Diallo
5,373 Points
Posted by Amadou Diallo
Amadou Diallo
5,373 Points

Why don't we just use INNER JOIN instead of INTERSECT?

Why don't we just use INNER JOIN instead of INTERSECT since they do, I think, the same thing?

1 Answer

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

They can have the same final result; but a JOIN adds an additional source to a single query based on specific matching criteria, and INTERSECT combines two complete queries (two SELECTs) that return identical columns.

Ryan Hartigan
Ryan Hartigan
3,425 Points
Ryan Hartigan
Ryan Hartigan
3,425 Points

What do you mean by an additional source to a single query?

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

I mean pulling data from the columns of two (or more) tables.