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create table #MyTable (
Col_A varchar(5),
Col_B int
)
insert into #MyTable values ('A',1)
insert into #MyTable values ('A',1)
insert into #MyTable values ('A',2)
insert into #MyTable values ('A',2)
insert into #MyTable values ('A',2)
insert into #MyTable values ('A',3)
insert into #MyTable values ('B',4)
insert into #MyTable values ('B',4)
insert into #MyTable values ('B',5)
9 rows affected
CREATE INDEX i ON #MyTable (Col_A, Col_B);
set statistics xml on;
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
-- GROUP BY mt2.Col_A
) AS ca;
| Col_A | Col_B | dc |
|---|---|---|
| A | 1 | 3 |
| A | 1 | 3 |
| A | 2 | 3 |
| A | 2 | 3 |
| A | 2 | 3 |
| A | 3 | 3 |
| B | 4 | 2 |
| B | 4 | 2 |
| B | 5 | 2 |
| Microsoft SQL Server 2005 XML Showplan |
|---|
| <ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.481" Build="14.0.3335.7"><BatchSequence><Batch><Statements><StmtSimple StatementText="SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
 FROM #MyTable AS mt2
 WHERE mt2.Col_A = mt.Col_A
 -- GROUP BY mt2.Col_A 
 ) AS ca" StatementId="1" StatementCompId="2" StatementType="SELECT" RetrievedFromCache="true" StatementSubTreeCost="0.00797214" StatementEstRows="9" SecurityPolicyApplied="false" StatementOptmLevel="FULL" QueryHash="0x76A40E7FE33C426B" QueryPlanHash="0x95D5E6BB777A4B52" StatementOptmEarlyAbortReason="GoodEnoughPlanFound" CardinalityEstimationModelVersion="140"><StatementSetOptions QUOTED_IDENTIFIER="true" ARITHABORT="true" CONCAT_NULL_YIELDS_NULL="true" ANSI_NULLS="true" ANSI_PADDING="true" ANSI_WARNINGS="true" NUMERIC_ROUNDABORT="false"></StatementSetOptions><QueryPlan DegreeOfParallelism="0" NonParallelPlanReason="NoParallelPlansInDesktopOrExpressEdition" CachedPlanSize="32" CompileTime="15" CompileCPU="15" CompileMemory="344"><MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0"></MemoryGrantInfo><OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="838808" EstimatedPagesCached="52425" EstimatedAvailableDegreeOfParallelism="1" MaxCompileMemory="904904"></OptimizerHardwareDependentProperties><OptimizerStatsUsage><StatisticsInfo LastUpdate="2020-11-03T17:12:34.90" ModificationCount="0" SamplingPercent="100" Statistics="[_WA_Sys_00000002_B5D7E539]" Table="[#MyTable____________________________________________________________________________________________________________0000000000BC]" Schema="[dbo]" Database="[tempdb]"></StatisticsInfo><StatisticsInfo LastUpdate="2020-11-03T17:12:34.89" ModificationCount="0" SamplingPercent="100" Statistics="[i]" Table="[#MyTable____________________________________________________________________________________________________________0000000000BC]" Schema="[dbo]" Database="[tempdb]"></StatisticsInfo></OptimizerStatsUsage><TraceFlags IsCompileTime="1"><TraceFlag Value="460" Scope="Global"></TraceFlag><TraceFlag Value="8017" Scope="Global"></TraceFlag></TraceFlags><TraceFlags IsCompileTime="0"><TraceFlag Value="460" Scope="Global"></TraceFlag><TraceFlag Value="8017" Scope="Global"></TraceFlag></TraceFlags><QueryTimeStats ElapsedTime="0" CpuTime="0"></QueryTimeStats><RelOp NodeId="0" PhysicalOp="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="9" EstimateIO="0" EstimateCPU="9e-007" AvgRowSize="21" EstimatedTotalSubtreeCost="0.00797214" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference><ColumnReference Column="Expr1004"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1004"></ColumnReference><ScalarOperator ScalarString="CASE WHEN [Expr1004] IS NULL THEN (0) ELSE [Expr1004] END"><IF><Condition><ScalarOperator><Logical Operation="IS NULL"><ScalarOperator><Identifier><ColumnReference Column="Expr1004"></ColumnReference></Identifier></ScalarOperator></Logical></ScalarOperator></Condition><Then><ScalarOperator><Const ConstValue="(0)"></Const></ScalarOperator></Then><Else><ScalarOperator><Identifier><ColumnReference Column="Expr1004"></ColumnReference></Identifier></ScalarOperator></Else></IF></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="1" PhysicalOp="Nested Loops" LogicalOp="Left Outer Join" EstimateRows="9" EstimateIO="0" EstimateCPU="3.762e-005" AvgRowSize="21" EstimatedTotalSubtreeCost="0.00797124" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference><ColumnReference Column="Expr1004"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><NestedLoops Optimized="0"><OuterReferences><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference></OuterReferences><RelOp NodeId="2" PhysicalOp="Index Scan" LogicalOp="Index Scan" EstimateRows="9" EstimatedRowsRead="9" EstimateIO="0.003125" EstimateCPU="0.0001669" AvgRowSize="17" EstimatedTotalSubtreeCost="0.0032919" TableCardinality="9" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="9" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="0" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference></DefinedValue><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference></DefinedValue></DefinedValues><Object Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Index="[i]" Alias="[mt]" IndexKind="NonClustered" Storage="RowStore"></Object></IndexScan></RelOp><RelOp NodeId="3" PhysicalOp="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="1" EstimateIO="0" EstimateCPU="0" AvgRowSize="11" EstimatedTotalSubtreeCost="0.00464172" Parallel="0" EstimateRebinds="4" EstimateRewinds="4" EstimatedExecutionMode="Row"><OutputList><ColumnReference Column="Expr1004"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1004"></ColumnReference><ScalarOperator ScalarString="CONVERT_IMPLICIT(int,[Expr1007],0)"><Convert DataType="int" Style="0" Implicit="1"><ScalarOperator><Identifier><ColumnReference Column="Expr1007"></ColumnReference></Identifier></ScalarOperator></Convert></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="4" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="1" EstimateIO="0" EstimateCPU="2.58594e-006" AvgRowSize="11" EstimatedTotalSubtreeCost="0.00464172" Parallel="0" EstimateRebinds="4" EstimateRewinds="4" EstimatedExecutionMode="Row"><OutputList><ColumnReference Column="Expr1007"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="0" ActualExecutions="9"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues><DefinedValue><ColumnReference Column="Expr1007"></ColumnReference><ScalarOperator ScalarString="COUNT([tempdb].[dbo].[#MyTable].[Col_B] as [mt2].[Col_B])"><Aggregate Distinct="0" AggType="COUNT_BIG"><ScalarOperator><Identifier><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></Identifier></ScalarOperator></Aggregate></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="5" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="3.47656" EstimateIO="0" EstimateCPU="3.98828e-006" AvgRowSize="11" EstimatedTotalSubtreeCost="0.00461844" Parallel="0" EstimateRebinds="4" EstimateRewinds="4" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="24" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="9" ActualExecutions="9"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues></DefinedValues><GroupBy><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></GroupBy><RelOp NodeId="6" PhysicalOp="Index Seek" LogicalOp="Index Seek" EstimateRows="4.5" EstimatedRowsRead="4.5" EstimateIO="0.003125" EstimateCPU="0.00016195" AvgRowSize="11" EstimatedTotalSubtreeCost="0.00458255" TableCardinality="9" Parallel="0" EstimateRebinds="4" EstimateRewinds="4" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="45" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="9" ActualLogicalReads="18" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="45" ActualEndOfScans="9" ActualExecutions="9"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></DefinedValue></DefinedValues><Object Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Index="[i]" Alias="[mt2]" IndexKind="NonClustered" Storage="RowStore"></Object><SeekPredicates><SeekPredicateNew><SeekKeys><Prefix ScanType="EQ"><RangeColumns><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference></RangeColumns><RangeExpressions><ScalarOperator ScalarString="[tempdb].[dbo].[#MyTable].[Col_A] as [mt].[Col_A]"><Identifier><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference></Identifier></ScalarOperator></RangeExpressions></Prefix></SeekKeys></SeekPredicateNew></SeekPredicates></IndexScan></RelOp></StreamAggregate></RelOp></StreamAggregate></RelOp></ComputeScalar></RelOp></NestedLoops></RelOp></ComputeScalar></RelOp></QueryPlan></StmtSimple></Statements></Batch></BatchSequence></ShowPlanXML> |
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
-- GROUP BY mt2.Col_A
) AS ca
SELECT
SELECT
| Cached plan size | 32 KB |
|---|---|
| Estimated Operator Cost | 0 (0%) |
| Estimated Subtree Cost | 0.0079721 |
| Degree of Parallelism | 0 |
| Estimated Number of Rows | 9 |
Statement
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
-- GROUP BY mt2.Col_A
) AS ca
Compute Scalar
Cost: 0%
Compute Scalar
Compute new values from existing values in a row.
| Physical Operation | Compute Scalar |
|---|---|
| Logical Operation | Compute Scalar |
| Estimated Execution Mode | Row |
| Estimated Operator Cost | 0.0000009 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000009 |
| Estimated Subtree Cost | 0.0079721 |
| Estimated Number of Executions | 1 |
| Estimated Number of Rows | 9 |
| Estimated Row Size | 21 B |
| Node ID | 0 |
Output List
[tempdb].[dbo].[#MyTable].[mt].Col_A
[tempdb].[dbo].[#MyTable].[mt].Col_B
Expr1004
Nested Loops
(Left Outer Join)
Cost: 0%
Nested Loops
For each row in the top (outer) input, scan the bottom (inner) input, and output matching rows.
| Physical Operation | Nested Loops |
|---|---|
| Logical Operation | Left Outer Join |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0000376 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000376 |
| Estimated Subtree Cost | 0.0079712 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 9 |
| Estimated Row Size | 21 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 1 |
Output List
[tempdb].[dbo].[#MyTable].[mt].Col_A
[tempdb].[dbo].[#MyTable].[mt].Col_B
Expr1004
Outer References
[tempdb].[dbo].[#MyTable].[mt].Col_A
Index Scan (NonClustered)
[#MyTable].[i].[mt]
Cost: 41%
Index Scan (NonClustered)
| Physical Operation | Index Scan |
|---|---|
| Logical Operation | Index Scan |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 9 |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032919 (41%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.0001669 |
| Estimated Subtree Cost | 0.0032919 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows to be Read | 9 |
| Estimated Number of Rows | 9 |
| Estimated Row Size | 17 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | False |
| Node ID | 2 |
Output List
[tempdb].[dbo].[#MyTable].[mt].Col_A
[tempdb].[dbo].[#MyTable].[mt].Col_B
Object
[tempdb].[dbo].[#MyTable].[i].[mt]
Compute Scalar
Cost: 0%
Compute Scalar
Compute new values from existing values in a row.
| Physical Operation | Compute Scalar |
|---|---|
| Logical Operation | Compute Scalar |
| Estimated Execution Mode | Row |
| Estimated Operator Cost | 0 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0 |
| Estimated Subtree Cost | 0.0046417 |
| Estimated Number of Executions | 5 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 11 B |
| Node ID | 3 |
Output List
Expr1004
Stream Aggregate
(Aggregate)
Cost: 0%
Stream Aggregate
Compute summary values for groups of rows in a suitably sorted stream.
| Physical Operation | Stream Aggregate |
|---|---|
| Logical Operation | Aggregate |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0000233 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000026 |
| Estimated Subtree Cost | 0.0046417 |
| Estimated Number of Executions | 5 |
| Number of Executions | 9 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 11 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 4 |
Output List
Expr1007
Stream Aggregate
(Aggregate)
Cost: 0%
Stream Aggregate
Compute summary values for groups of rows in a suitably sorted stream.
| Physical Operation | Stream Aggregate |
|---|---|
| Logical Operation | Aggregate |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 24 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0000359 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.000004 |
| Estimated Subtree Cost | 0.0046184 |
| Estimated Number of Executions | 5 |
| Number of Executions | 9 |
| Estimated Number of Rows | 3.47656 |
| Estimated Row Size | 11 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 5 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_B
Index Seek (NonClustered)
[#MyTable].[i].[mt2]
Cost: 57%
Index Seek (NonClustered)
Scan a particular range of rows from a nonclustered index.
| Physical Operation | Index Seek |
|---|---|
| Logical Operation | Index Seek |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 45 |
| Actual Number of Rows | 45 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0045826 (57%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.000162 |
| Estimated Subtree Cost | 0.0045826 |
| Estimated Number of Executions | 5 |
| Number of Executions | 9 |
| Estimated Number of Rows to be Read | 4.5 |
| Estimated Number of Rows | 4.5 |
| Estimated Row Size | 11 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 6 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_B
Object
[tempdb].[dbo].[#MyTable].[i].[mt2]
Seek Predicates
Seek Keys[1]: Prefix: [tempdb].[dbo].[#MyTable].Col_A = Scalar Operator([tempdb].[dbo].[#MyTable].[Col_A] as [mt].[Col_A])
set statistics xml on;
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
GROUP BY mt2.Col_A
) AS ca;
| Col_A | Col_B | dc |
|---|---|---|
| A | 1 | 3 |
| A | 1 | 3 |
| A | 2 | 3 |
| A | 2 | 3 |
| A | 2 | 3 |
| A | 3 | 3 |
| B | 4 | 2 |
| B | 4 | 2 |
| B | 5 | 2 |
| Microsoft SQL Server 2005 XML Showplan |
|---|
| <ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.481" Build="14.0.3335.7"><BatchSequence><Batch><Statements><StmtSimple StatementText="SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
 FROM #MyTable AS mt2
 WHERE mt2.Col_A = mt.Col_A
 GROUP BY mt2.Col_A 
 ) AS ca" StatementId="1" StatementCompId="2" StatementType="SELECT" RetrievedFromCache="true" StatementSubTreeCost="0.00678942" StatementEstRows="9" SecurityPolicyApplied="false" StatementOptmLevel="FULL" QueryHash="0xC6FF644F2AB61382" QueryPlanHash="0xEB6AA18104A755FE" StatementOptmEarlyAbortReason="GoodEnoughPlanFound" CardinalityEstimationModelVersion="140"><StatementSetOptions QUOTED_IDENTIFIER="true" ARITHABORT="true" CONCAT_NULL_YIELDS_NULL="true" ANSI_NULLS="true" ANSI_PADDING="true" ANSI_WARNINGS="true" NUMERIC_ROUNDABORT="false"></StatementSetOptions><QueryPlan DegreeOfParallelism="0" NonParallelPlanReason="NoParallelPlansInDesktopOrExpressEdition" CachedPlanSize="32" CompileTime="0" CompileCPU="0" CompileMemory="280"><MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0"></MemoryGrantInfo><OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="838808" EstimatedPagesCached="52425" EstimatedAvailableDegreeOfParallelism="1" MaxCompileMemory="904904"></OptimizerHardwareDependentProperties><OptimizerStatsUsage><StatisticsInfo LastUpdate="2020-11-03T17:12:34.89" ModificationCount="0" SamplingPercent="100" Statistics="[i]" Table="[#MyTable____________________________________________________________________________________________________________0000000000BC]" Schema="[dbo]" Database="[tempdb]"></StatisticsInfo></OptimizerStatsUsage><TraceFlags IsCompileTime="1"><TraceFlag Value="460" Scope="Global"></TraceFlag><TraceFlag Value="8017" Scope="Global"></TraceFlag></TraceFlags><TraceFlags IsCompileTime="0"><TraceFlag Value="460" Scope="Global"></TraceFlag><TraceFlag Value="8017" Scope="Global"></TraceFlag></TraceFlags><QueryTimeStats ElapsedTime="0" CpuTime="0"></QueryTimeStats><RelOp NodeId="0" PhysicalOp="Nested Loops" LogicalOp="Inner Join" EstimateRows="9" EstimateIO="0" EstimateCPU="3.762e-005" AvgRowSize="21" EstimatedTotalSubtreeCost="0.00678942" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference><ColumnReference Column="Expr1004"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><NestedLoops Optimized="0"><OuterReferences><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference></OuterReferences><RelOp NodeId="1" PhysicalOp="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="2" EstimateIO="0" EstimateCPU="0" AvgRowSize="16" EstimatedTotalSubtreeCost="0.0033029" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference><ColumnReference Column="Expr1004"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1004"></ColumnReference><ScalarOperator ScalarString="CONVERT_IMPLICIT(int,[Expr1007],0)"><Convert DataType="int" Style="0" Implicit="1"><ScalarOperator><Identifier><ColumnReference Column="Expr1007"></ColumnReference></Identifier></ScalarOperator></Convert></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="2" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="2" EstimateIO="0" EstimateCPU="4e-006" AvgRowSize="16" EstimatedTotalSubtreeCost="0.0033029" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference><ColumnReference Column="Expr1007"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="2" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues><DefinedValue><ColumnReference Column="Expr1007"></ColumnReference><ScalarOperator ScalarString="COUNT([tempdb].[dbo].[#MyTable].[Col_B] as [mt2].[Col_B])"><Aggregate Distinct="0" AggType="COUNT_BIG"><ScalarOperator><Identifier><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></Identifier></ScalarOperator></Aggregate></ScalarOperator></DefinedValue></DefinedValues><GroupBy><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference></GroupBy><RelOp NodeId="3" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="5" EstimateIO="0" EstimateCPU="7e-006" AvgRowSize="16" EstimatedTotalSubtreeCost="0.0032989" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="5" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues></DefinedValues><GroupBy><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></GroupBy><RelOp NodeId="4" PhysicalOp="Index Scan" LogicalOp="Index Scan" EstimateRows="9" EstimatedRowsRead="9" EstimateIO="0.003125" EstimateCPU="0.0001669" AvgRowSize="16" EstimatedTotalSubtreeCost="0.0032919" TableCardinality="9" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="9" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference></DefinedValue><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_B"></ColumnReference></DefinedValue></DefinedValues><Object Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Index="[i]" Alias="[mt2]" IndexKind="NonClustered" Storage="RowStore"></Object></IndexScan></RelOp></StreamAggregate></RelOp></StreamAggregate></RelOp></ComputeScalar></RelOp><RelOp NodeId="5" PhysicalOp="Index Seek" LogicalOp="Index Seek" EstimateRows="4.5" EstimatedRowsRead="4.5" EstimateIO="0.003125" EstimateCPU="0.00016195" AvgRowSize="17" EstimatedTotalSubtreeCost="0.0034489" TableCardinality="9" Parallel="0" EstimateRebinds="1" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="9" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="2" ActualLogicalReads="4" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="9" ActualEndOfScans="2" ActualExecutions="2"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference></DefinedValue><DefinedValue><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_B"></ColumnReference></DefinedValue></DefinedValues><Object Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Index="[i]" Alias="[mt]" IndexKind="NonClustered" Storage="RowStore"></Object><SeekPredicates><SeekPredicateNew><SeekKeys><Prefix ScanType="EQ"><RangeColumns><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt]" Column="Col_A"></ColumnReference></RangeColumns><RangeExpressions><ScalarOperator ScalarString="[tempdb].[dbo].[#MyTable].[Col_A] as [mt2].[Col_A]"><Identifier><ColumnReference Database="[tempdb]" Schema="[dbo]" Table="[#MyTable]" Alias="[mt2]" Column="Col_A"></ColumnReference></Identifier></ScalarOperator></RangeExpressions></Prefix></SeekKeys></SeekPredicateNew></SeekPredicates></IndexScan></RelOp></NestedLoops></RelOp></QueryPlan></StmtSimple></Statements></Batch></BatchSequence></ShowPlanXML> |
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
GROUP BY mt2.Col_A
) AS ca
SELECT
SELECT
| Cached plan size | 32 KB |
|---|---|
| Estimated Operator Cost | 0 (0%) |
| Estimated Subtree Cost | 0.0067894 |
| Degree of Parallelism | 0 |
| Estimated Number of Rows | 9 |
Statement
SELECT *
FROM #MyTable AS mt
CROSS APPLY ( SELECT COUNT(DISTINCT mt2.Col_B) AS dc
FROM #MyTable AS mt2
WHERE mt2.Col_A = mt.Col_A
GROUP BY mt2.Col_A
) AS ca
Nested Loops
(Inner Join)
Cost: 1%
Nested Loops
For each row in the top (outer) input, scan the bottom (inner) input, and output matching rows.
| Physical Operation | Nested Loops |
|---|---|
| Logical Operation | Inner Join |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0000376 (1%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000376 |
| Estimated Subtree Cost | 0.0067894 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 9 |
| Estimated Row Size | 21 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 0 |
Output List
[tempdb].[dbo].[#MyTable].[mt].Col_A
[tempdb].[dbo].[#MyTable].[mt].Col_B
Expr1004
Outer References
[tempdb].[dbo].[#MyTable].[mt2].Col_A
Compute Scalar
Cost: 0%
Compute Scalar
Compute new values from existing values in a row.
| Physical Operation | Compute Scalar |
|---|---|
| Logical Operation | Compute Scalar |
| Estimated Execution Mode | Row |
| Estimated Operator Cost | 0 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0 |
| Estimated Subtree Cost | 0.0033029 |
| Estimated Number of Executions | 1 |
| Estimated Number of Rows | 2 |
| Estimated Row Size | 16 B |
| Node ID | 1 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_A
Expr1004
Stream Aggregate
(Aggregate)
Cost: 0%
Stream Aggregate
Compute summary values for groups of rows in a suitably sorted stream.
| Physical Operation | Stream Aggregate |
|---|---|
| Logical Operation | Aggregate |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 2 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.000004 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.000004 |
| Estimated Subtree Cost | 0.0033029 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 2 |
| Estimated Row Size | 16 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 2 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_A
Expr1007
Stream Aggregate
(Aggregate)
Cost: 0%
Stream Aggregate
Compute summary values for groups of rows in a suitably sorted stream.
| Physical Operation | Stream Aggregate |
|---|---|
| Logical Operation | Aggregate |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 5 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.000007 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.000007 |
| Estimated Subtree Cost | 0.0032989 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 5 |
| Estimated Row Size | 16 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 3 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_A
[tempdb].[dbo].[#MyTable].[mt2].Col_B
Index Scan (NonClustered)
[#MyTable].[i].[mt2]
Cost: 48%
Index Scan (NonClustered)
| Physical Operation | Index Scan |
|---|---|
| Logical Operation | Index Scan |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 9 |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032919 (48%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.0001669 |
| Estimated Subtree Cost | 0.0032919 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows to be Read | 9 |
| Estimated Number of Rows | 9 |
| Estimated Row Size | 16 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 4 |
Output List
[tempdb].[dbo].[#MyTable].[mt2].Col_A
[tempdb].[dbo].[#MyTable].[mt2].Col_B
Object
[tempdb].[dbo].[#MyTable].[i].[mt2]
Index Seek (NonClustered)
[#MyTable].[i].[mt]
Cost: 51%
Index Seek (NonClustered)
Scan a particular range of rows from a nonclustered index.
| Physical Operation | Index Seek |
|---|---|
| Logical Operation | Index Seek |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 9 |
| Actual Number of Rows | 9 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0034489 (51%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.000162 |
| Estimated Subtree Cost | 0.0034489 |
| Estimated Number of Executions | 2 |
| Number of Executions | 2 |
| Estimated Number of Rows to be Read | 4.5 |
| Estimated Number of Rows | 4.5 |
| Estimated Row Size | 17 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 5 |
Output List
[tempdb].[dbo].[#MyTable].[mt].Col_A
[tempdb].[dbo].[#MyTable].[mt].Col_B
Object
[tempdb].[dbo].[#MyTable].[i].[mt]
Seek Predicates
Seek Keys[1]: Prefix: [tempdb].[dbo].[#MyTable].Col_A = Scalar Operator([tempdb].[dbo].[#MyTable].[Col_A] as [mt2].[Col_A])