perf(query): fuse no-WHERE multi-key count-only group-by#218
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ser-vasilich wants to merge 2 commits into
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perf(query): fuse no-WHERE multi-key count-only group-by#218ser-vasilich wants to merge 2 commits into
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The fused multi-key path already accepts a NULL predicate; only the planner gate required where_expr. Allow no-WHERE when n_keys >= 2 AND count-only. Single-key no-WHERE and multi-agg over near-unique composites stay on exec_group's radix — fusing them regresses at very high cardinality. ClickBench 10M: q16 744 → 154 ms total 8.0 → 7.3 s Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
mk_compile packs the composite by-key into a 16-byte slot. An I64
column for minute() (values 0..59) blows the budget on q18's
{UserID, minute, SearchPhrase} composite (~20 bytes) and the query
drops to exec_group.
After eval'ing a computed by-val whose AST head is minute / hh / ss /
dd / dow / mm / doy / yyyy, downcast the I64 result to I16 before
adding it to the table. I16 is the smallest type that holds every
output range (year up to 32767, doy up to 366) and still prints as
decimal (U8 prints hex, unreadable for a minute value).
Skipped when the source column has nulls.
ClickBench 10M:
q18 1748 → 449 ms
total 6.6 → 5.2 s
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Relax the fused group-by planner gate so a no-WHERE multi-key
count-only shape routes onto
exec_filtered_group_multiinstead ofthe unfused
exec_groupradix path.ray_filtered_groupalreadyaccepts a NULL predicate (worker runs with a const-true mask); the
only blocker was
where_expr &&in the gate.Gate now fires no-WHERE only when
n_keys >= 2 && has_only_count.Single-key no-WHERE and multi-agg over near-unique composites stay on
exec_group— at very high cardinality the radix path'sper-(worker, partition) scatter beats a single linear-probe shard.
Follow-up commit: narrow I64 results of known-small temporal extracts
(minute / hh / ss / dd / dow / mm / doy / yyyy) to I16 before adding
to the table. Brings q18's composite under the 16-byte mk_compile
budget so it fuses too.
ClickBench 10M: