Rewrite Query Store grid query using sp_QuickieStore patterns (#143)#145
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erikdarlingdata merged 1 commit intodevfrom Mar 25, 2026
Merged
Rewrite Query Store grid query using sp_QuickieStore patterns (#143)#145erikdarlingdata merged 1 commit intodevfrom
erikdarlingdata merged 1 commit intodevfrom
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Multi-phase materialization approach for drastically better performance on large Query Store datasets: Phase 1: Pre-filter matching interval IDs into #intervals (clustered PK). All subsequent phases use EXISTS semi-join against this tiny table instead of re-evaluating the time predicate. Phase 2: Aggregate runtime_stats by plan_id into #plan_stats (clustered PK on plan_id). Uses EXISTS against #intervals — semi-join avoids materializing the full interval join. Phase 3: Rank best plan per query_id, materialize TOP N into #top_plans. Still no nvarchar(max) columns touched. Phase 4: Hydrate only the TOP N winners with text, plan XML, and metadata. Uses TRY_CONVERT for safe plan XML handling. Additional improvements: - Both time filter paths now use rsi.start_time (indexed) instead of rs.last_execution_time (requires scanning all runtime_stats rows) - OPTION(RECOMPILE) on aggregation phases prevents parameter sniffing on date range parameters producing stale plans - Clustered PKs on temp tables enable index seeks in subsequent joins Tested on SQL2022: ~22ms total for all 4 phases (24 intervals, 546 plans). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This was referenced Mar 25, 2026
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Summary
Follow-up to PR #144 — the initial two-phase approach wasn't enough. This rewrites the query using patterns from sp_QuickieStore for significantly better performance on large Query Store datasets.
Four-phase materialization approach:
#intervals#plan_stats#top_plansAdditional improvements:
rsi.start_time(indexed) — thehoursBackfallback previously filtered onrs.last_execution_timewhich required scanning all runtime_statsPerformance
Tested on SQL2022 with PerformanceMonitor Query Store data: ~22ms total for all 4 phases (24 intervals, 546 plan aggregations, 5 winners hydrated).
Test plan
🤖 Generated with Claude Code