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… proven `DELETE FROM t ROWS (q)` retracts `t INTERSECT ALL q`, which reads and arranges all of `t`. When `q` is provably a sub-multiset of `t` at every timestamp, the intersection equals `q`, so the write can retract `q` directly and read only the collections `q` reads, for example a small materialized view of garbage rows. A new `SubMultiset` analysis in `mz-transform` proves containment conservatively over filters, identity projections, `EXCEPT ALL` and `INTERSECT ALL` shapes, and `Let` bindings. The adapter seeds it from the catalog: views and materialized views without a refresh schedule or replacement history count when their definitions are proven contained in the target table version. Anything else keeps the intersection. `mz_delete_rows_selection_total` counts which selection ran. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Local optimization pushes `Negate` below `Map` and `Project`, so the subtracted input of a planned `EXCEPT ALL` need not be a `Negate`. The intersection rule also proves `A INTERSECT ALL B` from `A` alone for any subtracted input. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Based on #40052.
DELETE FROM t ROWS (q)writesNegate(q)instead ofNegate(t INTERSECT ALL q)when it can prove thatqis a sub-multiset oft. The selection then reads onlyq, for example a small materialized view of rows due for cleanup, instead of scanning and arranging all oft.A new
SubMultisetMIR analysis inmz-transformdoes the proof. The adapter feeds it facts from the catalog: views by their definition, and materialized views only without a refresh schedule or replacement history. Unknown shapes fall back to the intersection. The OCC write atTlands only if the table is unchanged sinceT-1, so the proof holds at write time. The countermz_delete_rows_selection_totalrecords which path ran.🤖 Generated with Claude Code