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Multiset difference — EXCEPT ALL

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Multiset difference — EXCEPT ALL

src has rows where some values appear multiple times. tgt has fewer copies of some of those values. You need the "surplus" — for each value, how many MORE copies exist in src than in tgt.

Plain EXCEPT deduplicates and gives the wrong answer. EXCEPT ALL preserves multiplicity — that's what you need.

Columns: k. Sort by k ascending. Return one row per surplus copy.

Tables & sample data

src

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tgt

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query.sql

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