sp_QuickieStore: rewrite representative text query to avoid grouping on nvarchar(max)#701
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erikdarlingdata merged 3 commits intodevfrom Mar 23, 2026
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sp_QuickieStore: @find_high_impact output fixes
…on nvarchar(max) The #hi_representative_text query grouped by query_hash + query_sql_text, forcing the Hash Aggregate to hash nvarchar(max) values. Rewritten to group by query_hash + query_text_id (both fixed-width) in a subquery, then join back to query_store_query_text only for the rn=1 winner. Tested on SQL2022 and SQL2016. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
The
#hi_representative_textquery in@find_high_impactgrouped byquery_hash + query_sql_text, forcing the Hash Aggregate to hashnvarchar(max)values — slow and memory-hungry.Rewritten to:
query_hash + query_text_id(both fixed-width) in a subqueryrn = 1winnerquery_store_query_textonly for that single row per hashTest plan
🤖 Generated with Claude Code