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Results tagged with relational-calculus
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user 164228
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Intuition for a projection in tuple relational calculus
Equation for projection:
${ t ∣ ∃z ( R(z) ∧ t.name = z.name }$
Now, here we don't specify anywhere that $R(t)$ or $t \ belongs \ to \ relation \ R$. So, $t$ is basically just empty tuple with no speci …
