[thiagooak]

Summary

• This site runs Datomic Local through the Client API, which returns a vector with duplicate rows removed, not a set. Verified: a relation find's result class is PersistentVector.
• Cardinality-many's "returns a set of tuples" claim is now "removes duplicate rows"; find-specs.edn's "order within the set" (describing this site's own vector output) is now "order among the rows"; both leave "set" reserved for the Peer API discussion, which already correctly distinguishes it.
• Aggregations' "Datomic builds a set from the :find variables" is accurate as a description of the pre-aggregation mechanism, so it's left as-is, with "(plus :with variables)" added since :with variables are also part of that set.

Verification

• Ran the exact dual-type query from cardinality-many.edn through app.core/run-q: result class is PersistentVector, 67 entries, all distinct — confirms "duplicate rows are removed" is accurate.
• Ran the aggregations sum/:with example: sum jumps from 3070 to 9696 with :with ?e, confirming the pre-aggregation collapsing behavior the chapter describes.
• clojure -X:test: 32 tests, 493 assertions, 0 failures.

Closes #27

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