Fedor Ivanov
Reputation: 281
How semijoin is different from natural join + projection?
How semijoin is different from natural join + projection?
Upvotes: 1
Views: 1668
Answers (1)
Dan D.
Reputation: 74655
It isn't. A semijoin can be defined as a projection on a natural join.
See Wikipedia: Relational algebra / Semijoin
Upvotes: 1
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