Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Set-Theoretic Preliminaries for Computer Scientists   The basics of set theory are usually copied, directly or indirectly, by
computer scientists from introductions to mathematical texts. Often
mathematicians are content with special cases when the general case is of no
mathematical interest. But sometimes what is of no mathematical interest is of
great practical interest in computer science. For example, non-binary relations
in mathematics tend to have numerical indexes and tend to be unsorted. In the
theory and practice of relational databases both these simplifications are
unwarranted. In response to this situation we present here an alternative to
the ``set-theoretic preliminaries'' usually found in computer science texts.
This paper separates binary relations from the kind of relations that are
needed in relational databases. Its treatment of functions supports both
computer science in general and the kind of relations needed in databases. As a
sample application this paper shows how the mathematical theory of relations
naturally leads to the relational data model and how the operations on
relations are by themselves already a powerful vehicle for queries.

20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc