Tegiri Nenashi
  • Member for 11 years
  • Last seen more than a month ago
What videos should everybody watch?
11 votes

Quantum Information, Computation and Complexity

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What are recent advances in relational databases?
10 votes

In db query area arguably Provenance Semiring enjoyed the most attention recently. The "provenance" adjective is just marketing connecting it to a large body of research. Nevertheless the idea that ...

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Formal definition of parser?
10 votes

There is more in recognition that appears at the first sight. It is naturally generalized into recognizing all the substrings of a given string so that the output is a matrix A where matrix element A[...

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Canonical forms for relational algebra expressions
3 votes

Relational Lattice is axiomatic foundation for Relational Algebra. Predictably, query transformations reduce to equational reasoning in that axiom system. Here are examples: Push-select-via-project ...

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Measuring the randomness of CNF formulas
3 votes

I suggest to borrow physics intuition that "less random" structures are more symmetric. Symmetry for CNF is any transformation of the variables, that keeps the function invariant. By that criteria, ...

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First order expression for functional dependency
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2 votes

Apparently, we must project away variable z from ternary relation Q, which is done via existential quantifier: ∀y1∀y2∀x:(∃z:Q(x1,y,z))∧(∃z:Q(x2,y,z))⟹x1=x2. This is equivalent to standard textbook ...

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Is there a set theoretic way to look at SQL?
1 votes

It is common wisdom that database field is firmly grounded in the two math disciplines: predicate logic and set theory. However, this is very fuzzy observation, and reality is more subtle. The ...

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Natural computation based on fundamental forces
0 votes

Quantum theory captures the concept of discrete objects pretty well. Other physics theories don't.

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