removed singleton_lookup_count from calculations

also removed parameter @MinimumScanPctForComparison from the main script
MadeiraData · Jun 20, 2024 · afd2255 · afd2255
1 parent ac140fe
commit afd2255
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Showing 2 changed files with 7 additions and 12 deletions.
diff --git a/Indexes/Check Compression Candidate - Single Table.sql b/Indexes/Check Compression Candidate - Single Table.sql
@@ -25,8 +25,7 @@ SELECT
 					ISNULL(ios.leaf_delete_count,0) + 
 					ISNULL(ios.leaf_insert_count,0) + 
 					ISNULL(ios.leaf_page_merge_count,0) + 
-					ISNULL(ios.leaf_update_count,0) + 
-					ISNULL(ios.singleton_lookup_count,0)
+					ISNULL(ios.leaf_update_count,0)
 				), 0) * 100.0), 0)
 	, updates_percent = ISNULL(
 				CEILING(SUM(ISNULL(ios.leaf_update_count, 0)) * 1.0 /
@@ -35,8 +34,7 @@ SELECT
 					ISNULL(ios.leaf_delete_count,0) + 
 					ISNULL(ios.leaf_insert_count,0) + 
 					ISNULL(ios.leaf_page_merge_count,0) + 
-					ISNULL(ios.leaf_update_count,0) + 
-					ISNULL(ios.singleton_lookup_count,0)
+					ISNULL(ios.leaf_update_count,0)
 				), 0) * 100.0), 0)
 	, size_MB = CEILING(SUM(ISNULL(sps.in_row_data_page_count,0) + ISNULL(sps.row_overflow_used_page_count,0) + ISNULL(sps.lob_reserved_page_count,0)) / 128.0)
 	, in_row_percent = ISNULL(

diff --git a/Indexes/ultimate_compression_savings_estimation_whole_database.sql b/Indexes/ultimate_compression_savings_estimation_whole_database.sql
@@ -25,6 +25,7 @@
 ----------------------------------------------------------------
 -- Change Log:
 -- -----------
+-- 2024-06-20 - removed parameter @MinimumScanPctForComparison; removed singleton_lookup_count from calculation.
 -- 2021-09-09 - added check for incompatible options SortInTempDB and ResumableBuild being both enabled
 -- 2021-09-06 - added @ResumableRebuild parameter
 -- 2021-09-01 - some minor bug fixes and code quality fixes
@@ -98,7 +99,6 @@ DECLARE
 	-- Threshold parameters controlling recommendation algorithms based on partition stats:
 	,@MinimumCompressibleDataPercent	INT		= 45		-- Minimum percent of compressible in-row data, in order to consider any compression
 	,@MaximumUpdatePctAsInfrequent		INT		= 10		-- Maximum percent of updates for all operations to consider as "infrequent updates"
-	,@MinimumScanPctForComparison		INT		= 5		-- Minimum percent of range scans before considering to compare between update and scan percentages
 	,@MinimumScanPctForPage			INT		= 40		-- Minimum percent of scans when comparing to update percent, to deem PAGE compression preferable (otherwise, ROW compression will be preferable)
 	,@MaximumUpdatePctForPage		INT		= 40		-- Maximum percent of updates when comparing to scan percent, to deem PAGE compression preferable
 	,@MaximumUpdatePctForRow		INT		= 60		-- Maximum percent of updates when comparing to scan percent, to deem ROW compression preferable
@@ -176,7 +176,6 @@ FROM
 	,('@CompressionRatioThreshold',@CompressionRatioThreshold)
 	,('@MinimumRatioDifferenceForPage',@MinimumRatioDifferenceForPage)
 	,('@MaximumUpdatePctAsInfrequent',@MaximumUpdatePctAsInfrequent)
-	,('@MinimumScanPctForComparison',@MinimumScanPctForComparison)
 	,('@MaximumCPUPercentForRebuild',ISNULL(@MaximumCPUPercentForRebuild,100))
 ) AS v(VarName,VarValue)
 WHERE VarValue NOT BETWEEN 1 AND 100 OR VarValue IS NULL
@@ -420,8 +419,7 @@ SELECT
 					ISNULL(ios.leaf_delete_count,0) + 
 					ISNULL(ios.leaf_insert_count,0) + 
 					ISNULL(ios.leaf_page_merge_count,0) + 
-					ISNULL(ios.leaf_update_count,0) + 
-					ISNULL(ios.singleton_lookup_count,0)
+					ISNULL(ios.leaf_update_count,0)
 				), 0) * 100.0), 0)
 	, updates_percent = ISNULL(
 				CEILING(SUM(ISNULL(ios.leaf_update_count, 0)) * 1.0 /
@@ -430,8 +428,7 @@ SELECT
 					ISNULL(ios.leaf_delete_count,0) + 
 					ISNULL(ios.leaf_insert_count,0) + 
 					ISNULL(ios.leaf_page_merge_count,0) + 
-					ISNULL(ios.leaf_update_count,0) + 
-					ISNULL(ios.singleton_lookup_count,0)
+					ISNULL(ios.leaf_update_count,0)
 				), 0) * 100.0), 0)
 FROM #objects AS p WITH(NOLOCK)
 OUTER APPLY sys.dm_db_index_operational_stats(db_id(),p.object_id,p.index_id,p.partition_number) AS ios
@@ -502,7 +499,7 @@ BEGIN
 
 	SET @EstimationCheckRecommended = CASE
 						WHEN @InRowPercent < @MinimumCompressibleDataPercent THEN 0
-						WHEN ISNULL(@ScanPercent,0) <= @MinimumScanPctForComparison OR ISNULL(@UpdatePercent,0) <= @MaximumUpdatePctAsInfrequent THEN 1
+						WHEN ISNULL(@UpdatePercent,0) <= @MaximumUpdatePctAsInfrequent THEN 1
 						WHEN @CompressionType = 'PAGE' AND @ScanPercent >= @MinimumScanPctForPage AND @UpdatePercent <= @MaximumUpdatePctForPage THEN 1
 						WHEN @CompressionType = 'ROW' AND @UpdatePercent <= @MaximumUpdatePctForRow THEN 1
 						ELSE 0
@@ -646,7 +643,7 @@ SELECT
 						WHEN is_compression_recommended IS NULL AND is_compression_feasible = 1 THEN 
 						  CASE
 							WHEN in_row_percent < @MinimumCompressibleDataPercent THEN N'No'
-							WHEN compression_type = 'PAGE' AND ISNULL(scan_percent,0) <= @MinimumScanPctForComparison AND ISNULL(update_percent,0) <= @MaximumUpdatePctAsInfrequent THEN 'Yes'
+							WHEN compression_type = 'PAGE' AND ISNULL(update_percent,0) <= @MaximumUpdatePctAsInfrequent THEN 'Yes'
 							WHEN scan_percent >= @MinimumScanPctForPage AND update_percent <= @MaximumUpdatePctForPage THEN
 								CASE WHEN compression_type = 'PAGE' THEN 'Yes' ELSE 'No' END
 							WHEN update_percent <= @MaximumUpdatePctForRow THEN