2026-05-29 15:53:13 +02:00
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//! Physical operators for a small query-plan executor.
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//!
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2026-06-01 13:22:32 +02:00
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//! Three operators are in scope:
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//!
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//! - [`atom::scan_atom`] scans a [`table::Table`] under an
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//! [`atom::AtomPattern`], filtering for repeated-variable equality and
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//! literal equality, and outputs a binding [`relation::Relation`].
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//! - [`join::semijoin`] keeps rows of one relation whose shared-column values
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//! appear in another.
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//! - [`join::natural_join`] combines rows that agree on shared columns,
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//! emitting the union of their columns.
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//!
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//! Operators compose by function application; a "query plan written by hand"
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//! is just an expression like
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//! `natural_join(&semijoin(&a, &b), &scan_atom(&t, &p))`.
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//!
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//! Integration with an external query-plan IR is out of scope.
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pub mod atom;
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pub mod join;
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pub mod relation;
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pub mod table;
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pub mod value;
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