Selecting DISTINCT rows in relational algebra

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旧时难觅i
旧时难觅i 2021-01-08 00:33

There is a DISTINCT operator in SQL. However, I have an assignment in which I need to get some distinct values from a table, and I can only use relational algebra. Is there

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  •  孤街浪徒
    2021-01-08 01:12

    Relational Algebra is based on set theory. SQL is an implementation of multi-set theory. Set always has distinct elements. So tuples are distinct by default in Relational Algebra.

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