| id1 |
id2 |
| 1 |
null |
| 2 |
2 |
| null |
3 |
| 4 |
null |
| Microsoft SQL Server 2005 XML Showplan |
| <ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.564" Build="16.0.1000.6"><BatchSequence><Batch><Statements><StmtSimple StatementText="SELECT
 id1 = IIF(COUNT_BIG(*) = 2 OR MAX(U.src) = 1, U.id, NULL),
 id2 = IIF(COUNT_BIG(*) = 2 OR MAX(U.src) = 2, U.id, NULL)
FROM 
(
 SELECT src = 1, id FROM dbo.t1
 UNION ALL
 SELECT src = 2, id FROM dbo.t2
) AS U
GROUP BY 
 U.id
ORDER BY 
 U.id" StatementId="1" StatementCompId="2" StatementType="SELECT" StatementSqlHandle="0x0900476093A93E293EDA4F94E935562C5B640000000000000000000000000000000000000000000000000000" DatabaseContextSettingsId="2" ParentObjectId="0" StatementParameterizationType="0" RetrievedFromCache="true" StatementSubTreeCost="0.0121862" StatementEstRows="3.66667" SecurityPolicyApplied="false" StatementOptmLevel="FULL" QueryHash="0xFBCADA2741BACFA8" QueryPlanHash="0xE303F8E5D7E33816" StatementOptmEarlyAbortReason="GoodEnoughPlanFound" CardinalityEstimationModelVersion="160"><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="93" CompileCPU="15" CompileMemory="336"><MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0" GrantedMemory="0" MaxUsedMemory="0"></MemoryGrantInfo><OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="1258238" EstimatedPagesCached="78639" EstimatedAvailableDegreeOfParallelism="1" MaxCompileMemory="1042384"></OptimizerHardwareDependentProperties><OptimizerStatsUsage><StatisticsInfo LastUpdate="2023-03-19T12:31:45.68" ModificationCount="0" SamplingPercent="100" Statistics="[PK__t2__3213E83FB4C6A4EB]" Table="[t2]" Schema="[dbo]" Database="[fiddle_10444253a2834570a0187cd73de8164c]"></StatisticsInfo><StatisticsInfo LastUpdate="2023-03-19T12:31:45.67" ModificationCount="0" SamplingPercent="100" Statistics="[PK__t1__3213E83F58D86692]" Table="[t1]" Schema="[dbo]" Database="[fiddle_10444253a2834570a0187cd73de8164c]"></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="3.66667" EstimateIO="0" EstimateCPU="3.66667e-07" AvgRowSize="19" EstimatedTotalSubtreeCost="0.0121862" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Column="Union1007"></ColumnReference><ColumnReference Column="Expr1010"></ColumnReference><ColumnReference Column="Expr1011"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1010"></ColumnReference><ScalarOperator ScalarString="CASE WHEN [Expr1008]=(2) OR [Expr1009]=(1) THEN [Union1007] ELSE NULL END"><IF><Condition><ScalarOperator><Logical Operation="OR"><ScalarOperator><Compare CompareOp="EQ"><ScalarOperator><Identifier><ColumnReference Column="Expr1008"></ColumnReference></Identifier></ScalarOperator><ScalarOperator><Const ConstValue="(2)"></Const></ScalarOperator></Compare></ScalarOperator><ScalarOperator><Compare CompareOp="EQ"><ScalarOperator><Identifier><ColumnReference Column="Expr1009"></ColumnReference></Identifier></ScalarOperator><ScalarOperator><Const ConstValue="(1)"></Const></ScalarOperator></Compare></ScalarOperator></Logical></ScalarOperator></Condition><Then><ScalarOperator><Identifier><ColumnReference Column="Union1007"></ColumnReference></Identifier></ScalarOperator></Then><Else><ScalarOperator><Const ConstValue="NULL"></Const></ScalarOperator></Else></IF></ScalarOperator></DefinedValue><DefinedValue><ColumnReference Column="Expr1011"></ColumnReference><ScalarOperator ScalarString="CASE WHEN [Expr1008]=(2) OR [Expr1009]=(2) THEN [Union1007] ELSE NULL END"><IF><Condition><ScalarOperator><Logical Operation="OR"><ScalarOperator><Compare CompareOp="EQ"><ScalarOperator><Identifier><ColumnReference Column="Expr1008"></ColumnReference></Identifier></ScalarOperator><ScalarOperator><Const ConstValue="(2)"></Const></ScalarOperator></Compare></ScalarOperator><ScalarOperator><Compare CompareOp="EQ"><ScalarOperator><Identifier><ColumnReference Column="Expr1009"></ColumnReference></Identifier></ScalarOperator><ScalarOperator><Const ConstValue="(2)"></Const></ScalarOperator></Compare></ScalarOperator></Logical></ScalarOperator></Condition><Then><ScalarOperator><Identifier><ColumnReference Column="Union1007"></ColumnReference></Identifier></ScalarOperator></Then><Else><ScalarOperator><Const ConstValue="NULL"></Const></ScalarOperator></Else></IF></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="1" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="3.66667" EstimateIO="0" EstimateCPU="4.83333e-06" AvgRowSize="23" EstimatedTotalSubtreeCost="0.0121858" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Column="Union1007"></ColumnReference><ColumnReference Column="Expr1008"></ColumnReference><ColumnReference Column="Expr1009"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="4" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues><DefinedValue><ColumnReference Column="Expr1008"></ColumnReference><ScalarOperator ScalarString="Count(*)"><Aggregate AggType="countstar" Distinct="0"></Aggregate></ScalarOperator></DefinedValue><DefinedValue><ColumnReference Column="Expr1009"></ColumnReference><ScalarOperator ScalarString="MAX([Union1006])"><Aggregate Distinct="0" AggType="MAX"><ScalarOperator><Identifier><ColumnReference Column="Union1006"></ColumnReference></Identifier></ScalarOperator></Aggregate></ScalarOperator></DefinedValue></DefinedValues><GroupBy><ColumnReference Column="Union1007"></ColumnReference></GroupBy><RelOp NodeId="2" PhysicalOp="Merge Join" LogicalOp="Concatenation" EstimateRows="5" EstimateIO="0" EstimateCPU="0.005611" AvgRowSize="15" EstimatedTotalSubtreeCost="0.012181" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Column="Union1007"></ColumnReference><ColumnReference Column="Union1006"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="5" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualScans="0" ActualLogicalReads="0" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><Merge><DefinedValues><DefinedValue><ColumnReference Column="Union1007"></ColumnReference><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t1]" Column="id"></ColumnReference><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t2]" Column="id"></ColumnReference></DefinedValue><DefinedValue><ColumnReference Column="Union1006"></ColumnReference><ColumnReference Column="Expr1002"></ColumnReference><ColumnReference Column="Expr1005"></ColumnReference></DefinedValue></DefinedValues><RelOp NodeId="3" PhysicalOp="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="3" EstimateIO="0" EstimateCPU="3e-07" AvgRowSize="15" EstimatedTotalSubtreeCost="0.0032856" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t1]" Column="id"></ColumnReference><ColumnReference Column="Expr1002"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1002"></ColumnReference><ScalarOperator ScalarString="(1)"><Const ConstValue="(1)"></Const></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="4" PhysicalOp="Clustered Index Scan" LogicalOp="Clustered Index Scan" EstimateRows="3" EstimatedRowsRead="3" EstimateIO="0.003125" EstimateCPU="0.0001603" AvgRowSize="11" EstimatedTotalSubtreeCost="0.0032853" TableCardinality="3" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t1]" Column="id"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="3" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="3" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t1]" Column="id"></ColumnReference></DefinedValue></DefinedValues><Object Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t1]" Index="[PK__t1__3213E83F58D86692]" IndexKind="Clustered" Storage="RowStore"></Object></IndexScan></RelOp></ComputeScalar></RelOp><RelOp NodeId="5" PhysicalOp="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="2" EstimateIO="0" EstimateCPU="2e-07" AvgRowSize="15" EstimatedTotalSubtreeCost="0.0032844" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t2]" Column="id"></ColumnReference><ColumnReference Column="Expr1005"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1005"></ColumnReference><ScalarOperator ScalarString="(2)"><Const ConstValue="(2)"></Const></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="6" PhysicalOp="Clustered Index Scan" LogicalOp="Clustered Index Scan" EstimateRows="2" EstimatedRowsRead="2" EstimateIO="0.003125" EstimateCPU="0.0001592" AvgRowSize="11" EstimatedTotalSubtreeCost="0.0032842" TableCardinality="2" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t2]" Column="id"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="2" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="2" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t2]" Column="id"></ColumnReference></DefinedValue></DefinedValues><Object Database="[fiddle_10444253a2834570a0187cd73de8164c]" Schema="[dbo]" Table="[t2]" Index="[PK__t2__3213E83FB4C6A4EB]" IndexKind="Clustered" Storage="RowStore"></Object></IndexScan></RelOp></ComputeScalar></RelOp></Merge></RelOp></StreamAggregate></RelOp></ComputeScalar></RelOp></QueryPlan></StmtSimple></Statements></Batch></BatchSequence></ShowPlanXML> |