Duality between Set and Join Operators For two tables A and B with the same columns, set intersection select * from A intersect select * from B can be expressed as a semi-join select distinct * from A where (col1,col2,…) in (select col1,col2,… from B) Likewise, set difference select * from A intersect select * from B can be expressed as an anti-join select distinct * from A where (col1,col2,…) not in (select col1,col2,… from B) Transforming set into join operators expands optimizer search space. Optimizer could explore new, previously unavailable join order permutations - Study24x7
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Duality between Set and Join Operators For two tables A and B with the same columns, set intersection select * from A intersect select * from B can be expressed as a semi-join select distinct * from A where (col1,col2,…) in (select col1,col2,… from B) Likewise, set difference...

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