SQL Server 2008r2全体でインデックスシークを使用して完全に正常に実行されている非常に基本的なクエリがあります。 SQL Server 2017に移行すると、パフォーマンスが低下し始め、以前は問題がなかったクエリのRemote_Record全体でクラスター化インデックススキャンが実行されるため、残りのクエリが1分以上実行されます関数が適用されるレコードの数。これは、アップグレードのわずか数秒で完了しました。レガシーCardinality Estimatorを使用するように切り替えると、プランが元に戻りましたが、それは避けたいオプションです。
また、SQL Server 2019に対してもテストしましたが、Local_Record_Additional_Dataでのクラスター化インデックスシークがRowStore処理でバッチモードを使用してシークを取得することを除いて、SQL 2008r2と同じタイプのプランに戻りました。
SQL 2017のクエリでTOP 1を使用することで、Remote_Recordsでクラスター化インデックススキャンを使用しないようにクエリを取得できますが、これはSQL 2008r2で追加の変更なしに機能したため、カーディナリティエスティメーターがなぜか途方に暮れていますこの場合はオフです。
このクエリは、表示する特定のデータを収集するために特定のID値に対して適用される、より大きなインラインテーブル値関数の一部です。これは、問題のある機能の唯一の部分です。
任意のアドバイスをいただければ幸いです。
実行計画のリンクは次のとおりです。元のSQL 2008r2計画: https://www.brentozar.com/pastetheplan/?id=S1G4pnK2H
元のSQL 2017プラン: https://www.brentozar.com/pastetheplan/?id=B1ALKXQ2S
SQL 2017とTF 9481: https://www.brentozar.com/pastetheplan/?id=ByguM2Y2S
マイクロソフトはSQL 2019のDTDを公開していません。SQL2019計画に以下のXMLを含めました。
本番環境で表示されている内容を反映するテーブルとデータセットを生成するコード:
CREATE TABLE Remote_Records
(
Remote_record_id int identity (1,1) PRIMARY KEY CLUSTERED,
Bit_1 bit,
Bit_2 bit
)
GO
CREATE TABLE Local_Record_Additional_Data
(
Local_record_id int identity(1,1) PRIMARY KEY CLUSTERED,
Status_data varchar(100),
Device_data varchar(25)
)
GO
CREATE TABLE Remote_Additional_Data
(
Remote_add_data_id int identity(1,1) PRIMARY KEY CLUSTERED,
Remote_record_id int NOT NULL CONSTRAINT FK_Remote_Additional_Data_Remote_Records_Remote_record_id FOREIGN KEY (Remote_record_id) REFERENCES Remote_Records(Remote_record_id),
Local_record_add_id int NULL CONSTRAINT FK_Remote_Additional_Data_Local_Record_Additional_Data FOREIGN KEY (Local_record_add_id) REFERENCES Local_Record_Additional_Data(Local_record_id)
)
GO
DECLARE @count int = 1
WHILE @count <=319756
BEGIN
INSERT INTO Remote_Records
SELECT 0,0
SET @count = @count + 1
END
GO
DECLARE @count int = 1
WHILE @count <=457
BEGIN
INSERT INTO Local_Record_Additional_Data(Status_data,Device_data)
SELECT NULL,NULL
SET @count = @count + 1
END
GO
DECLARE @count int = 2
DECLARE @count_2 int = 1
DECLARE @rr_id int
DECLARE @max_rr_id int
DECLARE @rad_id int = 1
DECLARE @lrad_id int
SELECT @max_rr_id = max(Remote_record_id) FROM Remote_Records
WHILE @count <= 486004
BEGIN
IF @count > @max_rr_id
BEGIN
SET @count_2 = @count_2 + 1
END
IF @count >= 486004-456
BEGIN
SET @lrad_id = ISNULL(@lrad_id,0) + 1
END
SELECT @rr_id = CASE WHEN @count > @max_rr_id THEN @count_2 ELSE @count END
INSERT INTO Remote_Additional_Data(Remote_record_id, Local_record_add_id)
SELECT @rr_id, @lrad_id
SET @count = @count + 1
END
GO
sp_createstats 'NO','NO','NORECOMPUTE'
GO
UPDATE STATISTICS Remote_Records WITH FULLSCAN
GO
UPDATE STATISTICS Local_Record_Additional_Data WITH FULLSCAN
GO
UPDATE STATISTICS Remote_Additional_Data WITH FULLSCAN
GO
CREATE INDEX IX_Remote_Additional_Data_Remote_record_id ON [Remote_Additional_Data](Remote_record_id) INCLUDE (Local_record_add_id)
GO
CREATE INDEX IX_Remote_Additional_Data_Local_record_add_id ON [Remote_Additional_Data](Local_record_add_id) INCLUDE (Remote_record_id)
GO
これが問題のクエリです。
declare @lra_id int = 267
SELECT Local_record_add_id,
Bit_1,
Bit_2
FROM Remote_records se
INNER JOIN Remote_Additional_Data foe ON se.Remote_record_id = foe.Remote_record_id
INNER JOIN Local_Record_Additional_Data foh on foe.Local_record_add_id = foh.Local_record_id
WHERE foe.Local_record_add_id = @lra_id
go
SQL 2019実行プランXML:
<?xml version="1.0" encoding="utf-16"?>
<ShowPlanXML xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" Version="1.539" Build="15.0.2000.5" xmlns="http://schemas.Microsoft.com/sqlserver/2004/07/showplan">
<BatchSequence>
<Batch>
<Statements>
<StmtSimple StatementCompId="2" StatementEstRows="1" StatementId="1" StatementOptmLevel="FULL" StatementOptmEarlyAbortReason="GoodEnoughPlanFound" CardinalityEstimationModelVersion="150" StatementSubTreeCost="0.00985766" StatementText="SELECT Local_record_add_id,
 Bit_1,
 Bit_2
 FROM Remote_records se 
 INNER JOIN Remote_Additional_Data foe ON se.Remote_record_id = foe.Remote_record_id
 INNER JOIN Local_Record_Additional_Data foh on foe.Local_record_add_id = foh.Local_record_id
 WHERE foe.Local_record_add_id = @lra_id" StatementType="SELECT" QueryHash="0x6825DB46BFFA067E" QueryPlanHash="0xE4DD43257F5DD402" RetrievedFromCache="false" SecurityPolicyApplied="false" BatchModeOnRowStoreUsed="true">
<StatementSetOptions ANSI_NULLS="true" ANSI_PADDING="true" ANSI_WARNINGS="true" ARITHABORT="true" CONCAT_NULL_YIELDS_NULL="true" NUMERIC_ROUNDABORT="false" QUOTED_IDENTIFIER="true" />
<QueryPlan DegreeOfParallelism="1" CachedPlanSize="32" CompileTime="8" CompileCPU="8" CompileMemory="376">
<MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0" GrantedMemory="0" MaxUsedMemory="0" />
<OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="102400" EstimatedPagesCached="153600" EstimatedAvailableDegreeOfParallelism="12" MaxCompileMemory="18406536" />
<OptimizerStatsUsage>
<StatisticsInfo Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Statistics="[Local_record_add_id]" ModificationCount="0" SamplingPercent="100" LastUpdate="2019-11-21T13:25:16.28" />
<StatisticsInfo Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Statistics="[IX_Remote_Additional_Data_Remote_record_id]" ModificationCount="0" SamplingPercent="100" LastUpdate="2019-11-21T13:25:16.5" />
<StatisticsInfo Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Statistics="[Remote_record_id]" ModificationCount="0" SamplingPercent="100" LastUpdate="2019-11-21T13:25:15.86" />
<StatisticsInfo Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Statistics="[IX_Remote_Additional_Data_Local_record_add_id]" ModificationCount="0" SamplingPercent="100" LastUpdate="2019-11-21T13:25:17.78" />
<StatisticsInfo Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Statistics="[PK__Remote_R__FEF044CF617642DF]" ModificationCount="0" SamplingPercent="100" LastUpdate="2019-11-21T13:25:14.75" />
</OptimizerStatsUsage>
<QueryTimeStats CpuTime="0" ElapsedTime="0" />
<RelOp AvgRowSize="12" EstimateCPU="4.18E-06" EstimateIO="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row" EstimateRows="1" LogicalOp="Inner Join" NodeId="0" Parallel="false" PhysicalOp="Nested Loops" EstimatedTotalSubtreeCost="0.00985766">
<OutputList>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_1" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_2" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Local_record_add_id" />
</OutputList>
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="1" Batches="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" />
</RunTimeInformation>
<NestedLoops Optimized="false">
<RelOp AvgRowSize="9" EstimateCPU="0.0001581" EstimateIO="0.003125" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Batch" EstimateRows="1" EstimatedRowsRead="1" LogicalOp="Clustered Index Seek" NodeId="2" Parallel="false" PhysicalOp="Clustered Index Seek" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="457">
<OutputList />
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="1" ActualRowsRead="1" Batches="1" ActualEndOfScans="0" ActualExecutions="1" ActualExecutionMode="Batch" ActualElapsedms="0" ActualCPUms="0" ActualScans="0" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" />
</RunTimeInformation>
<IndexScan Ordered="true" ScanDirection="FORWARD" ForcedIndex="false" ForceSeek="false" ForceScan="false" NoExpandHint="false" Storage="RowStore">
<DefinedValues />
<Object Database="[Stats_Testing]" Schema="[dbo]" Table="[Local_Record_Additional_Data]" Index="[PK__Local_Re__E377E55CA10BE177]" Alias="[foh]" IndexKind="Clustered" Storage="RowStore" />
<SeekPredicates>
<SeekPredicateNew>
<SeekKeys>
<Prefix ScanType="EQ">
<RangeColumns>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Local_Record_Additional_Data]" Alias="[foh]" Column="Local_record_id" />
</RangeColumns>
<RangeExpressions>
<ScalarOperator ScalarString="[@lra_id]">
<Identifier>
<ColumnReference Column="@lra_id" />
</Identifier>
</ScalarOperator>
</RangeExpressions>
</Prefix>
</SeekKeys>
</SeekPredicateNew>
</SeekPredicates>
</IndexScan>
</RelOp>
<RelOp AvgRowSize="12" EstimateCPU="4.18E-06" EstimateIO="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row" EstimateRows="1" LogicalOp="Inner Join" NodeId="3" Parallel="false" PhysicalOp="Nested Loops" EstimatedTotalSubtreeCost="0.00657038">
<OutputList>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_1" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_2" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Local_record_add_id" />
</OutputList>
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="1" Batches="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" />
</RunTimeInformation>
<NestedLoops Optimized="false">
<OuterReferences>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Remote_record_id" />
</OuterReferences>
<RelOp AvgRowSize="15" EstimateCPU="0.0001581" EstimateIO="0.003125" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row" EstimateRows="1" EstimatedRowsRead="1" LogicalOp="Index Seek" NodeId="4" Parallel="false" PhysicalOp="Index Seek" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="486003">
<OutputList>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Remote_record_id" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Local_record_add_id" />
</OutputList>
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="1" ActualRowsRead="1" Batches="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="3" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" />
</RunTimeInformation>
<IndexScan Ordered="true" ScanDirection="FORWARD" ForcedIndex="false" ForceSeek="false" ForceScan="false" NoExpandHint="false" Storage="RowStore">
<DefinedValues>
<DefinedValue>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Remote_record_id" />
</DefinedValue>
<DefinedValue>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Local_record_add_id" />
</DefinedValue>
</DefinedValues>
<Object Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Index="[IX_Remote_Additional_Data_Local_record_add_id]" Alias="[foe]" IndexKind="NonClustered" Storage="RowStore" />
<SeekPredicates>
<SeekPredicateNew>
<SeekKeys>
<Prefix ScanType="EQ">
<RangeColumns>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Local_record_add_id" />
</RangeColumns>
<RangeExpressions>
<ScalarOperator ScalarString="[@lra_id]">
<Identifier>
<ColumnReference Column="@lra_id" />
</Identifier>
</ScalarOperator>
</RangeExpressions>
</Prefix>
</SeekKeys>
</SeekPredicateNew>
</SeekPredicates>
</IndexScan>
</RelOp>
<RelOp AvgRowSize="9" EstimateCPU="0.0001581" EstimateIO="0.003125" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row" EstimateRows="1" EstimatedRowsRead="1" LogicalOp="Clustered Index Seek" NodeId="5" Parallel="false" PhysicalOp="Clustered Index Seek" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="319756">
<OutputList>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_1" />
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_2" />
</OutputList>
<RunTimeInformation>
<RunTimeCountersPerThread Thread="0" ActualRows="1" ActualRowsRead="1" Batches="0" ActualEndOfScans="0" ActualExecutions="1" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="0" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" />
</RunTimeInformation>
<IndexScan Ordered="true" ScanDirection="FORWARD" ForcedIndex="false" ForceSeek="false" ForceScan="false" NoExpandHint="false" Storage="RowStore">
<DefinedValues>
<DefinedValue>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_1" />
</DefinedValue>
<DefinedValue>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Bit_2" />
</DefinedValue>
</DefinedValues>
<Object Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Index="[PK__Remote_R__FEF044CF617642DF]" Alias="[se]" IndexKind="Clustered" Storage="RowStore" />
<SeekPredicates>
<SeekPredicateNew>
<SeekKeys>
<Prefix ScanType="EQ">
<RangeColumns>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Records]" Alias="[se]" Column="Remote_record_id" />
</RangeColumns>
<RangeExpressions>
<ScalarOperator ScalarString="[Stats_Testing].[dbo].[Remote_Additional_Data].[Remote_record_id] as [foe].[Remote_record_id]">
<Identifier>
<ColumnReference Database="[Stats_Testing]" Schema="[dbo]" Table="[Remote_Additional_Data]" Alias="[foe]" Column="Remote_record_id" />
</Identifier>
</ScalarOperator>
</RangeExpressions>
</Prefix>
</SeekKeys>
</SeekPredicateNew>
</SeekPredicates>
</IndexScan>
</RelOp>
</NestedLoops>
</RelOp>
</NestedLoops>
</RelOp>
<ParameterList>
<ColumnReference Column="@lra_id" ParameterDataType="int" ParameterRuntimeValue="(267)" />
</ParameterList>
</QueryPlan>
</StmtSimple>
</Statements>
</Batch>
</BatchSequence>
</ShowPlanXML>
これは、2017年のホットフィックスの1つを使用してMicrosoftによって修正されたようです。TF4199を有効にした後、実行プランは予想どおりに切り替わりました。