sp_IndexCleanup: stage dm_db_index_usage_stats to fix 4-minute scan#719
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erikdarlingdata merged 3 commits intodevfrom Mar 25, 2026
Merged
sp_IndexCleanup: stage dm_db_index_usage_stats to fix 4-minute scan#719erikdarlingdata merged 3 commits intodevfrom
erikdarlingdata merged 3 commits intodevfrom
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sp_QuickieStore: @find_high_impact performance overhaul (60s → 10s)
…scans The LEFT JOIN to dm_db_index_usage_stats was executed via nested loops, scanning the full DMV per row (52M actual rows, ~4 minutes). Now pre-stages the DMV for the current database into #usage_stats with a clustered PK on (object_id, index_id) before the main query, then LEFT JOINs to the temp table instead. Handles the database cursor loop with TRUNCATE on re-entry. Tested on SQL2022 (StackOverflow2013) and SQL2016 (StackOverflow2010). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Pre-stages
dm_db_index_usage_statsfor the current database into#usage_statswith clustered PK, replacing the direct LEFT JOIN that caused 52M-row nested loop scans (~4 minutes).Test plan
🤖 Generated with Claude Code