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DECLARE @Target table
(
c1 integer PRIMARY KEY,
c2 integer NOT NULL,
c3 integer NOT NULL
);
DECLARE @Source table
(
c1 integer NULL,
c2 integer NULL,
c3 integer NULL,
INDEX c CLUSTERED (c1)
);
INSERT @Target
(c1, c2, c3)
VALUES
(1, 0, 0);
INSERT @Source
(c1, c2, c3)
VALUES
(1, 2, NULL),
(1, NULL, 3);
set statistics xml on;
UPDATE T
SET T.c2 = S.c2,
T.c3 = S.c3
FROM @Target AS T
JOIN @Source AS S
ON S.c1 = T.c1
--OPTION (HASH GROUP)
| Microsoft SQL Server 2005 XML Showplan |
|---|
| <ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.481" Build="14.0.3451.2"><BatchSequence><Batch><Statements><StmtSimple StatementText="UPDATE T
SET T.c2 = S.c2,
 T.c3 = S.c3
FROM @Target AS T
JOIN @Source AS S
 ON S.c1 = T.c1" StatementId="1" StatementCompId="6" StatementType="UPDATE" RetrievedFromCache="true" StatementSubTreeCost="0.0165724" StatementEstRows="1" SecurityPolicyApplied="false" StatementOptmLevel="FULL" QueryHash="0xB43E740E769130B6" QueryPlanHash="0xD7858543293275C5" 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="CouldNotGenerateValidParallelPlan" CachedPlanSize="32" CompileTime="15" CompileCPU="15" CompileMemory="296"><MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0"></MemoryGrantInfo><OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="1258238" EstimatedPagesCached="78639" EstimatedAvailableDegreeOfParallelism="1" MaxCompileMemory="3643384"></OptimizerHardwareDependentProperties><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="Clustered Index Update" LogicalOp="Update" EstimateRows="1" EstimateIO="0.01" EstimateCPU="1e-006" AvgRowSize="9" EstimatedTotalSubtreeCost="0.0165724" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="1" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="0" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="1" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><Update DMLRequestSort="0"><Object Table="[@Target]" Index="[PK__#B4C8175__3213663B89F164C7]" Alias="[T]" Storage="RowStore"></Object><SetPredicate><ScalarOperator ScalarString="@Target.[c2] as [T].[c2] = RaiseIfNullUpdate(@Source.[c2] as [S].[c2]),@Target.[c3] as [T].[c3] = RaiseIfNullUpdate(@Source.[c3] as [S].[c3])"><ScalarExpressionList><ScalarOperator><MultipleAssign><Assign><ColumnReference Table="@Target" Alias="[T]" Column="c2"></ColumnReference><ScalarOperator><Intrinsic FunctionName="RaiseIfNullUpdate"><ScalarOperator><Identifier><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference></Identifier></ScalarOperator></Intrinsic></ScalarOperator></Assign><Assign><ColumnReference Table="@Target" Alias="[T]" Column="c3"></ColumnReference><ScalarOperator><Intrinsic FunctionName="RaiseIfNullUpdate"><ScalarOperator><Identifier><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></Identifier></ScalarOperator></Intrinsic></ScalarOperator></Assign></MultipleAssign></ScalarOperator></ScalarExpressionList></ScalarOperator></SetPredicate><RelOp NodeId="1" PhysicalOp="Stream Aggregate" LogicalOp="Aggregate" EstimateRows="1" EstimateIO="0" EstimateCPU="1e-006" AvgRowSize="19" EstimatedTotalSubtreeCost="0.00657138" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="1" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><StreamAggregate><DefinedValues><DefinedValue><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference><ScalarOperator ScalarString="ANY(@Source.[c2] as [S].[c2])"><Aggregate Distinct="0" AggType="ANY"><ScalarOperator><Identifier><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference></Identifier></ScalarOperator></Aggregate></ScalarOperator></DefinedValue><DefinedValue><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference><ScalarOperator ScalarString="ANY(@Source.[c3] as [S].[c3])"><Aggregate Distinct="0" AggType="ANY"><ScalarOperator><Identifier><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></Identifier></ScalarOperator></Aggregate></ScalarOperator></DefinedValue></DefinedValues><GroupBy><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference></GroupBy><RelOp NodeId="2" PhysicalOp="Nested Loops" LogicalOp="Inner Join" EstimateRows="1" EstimateIO="0" EstimateCPU="4.18e-006" AvgRowSize="19" EstimatedTotalSubtreeCost="0.00657038" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="2" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><NestedLoops Optimized="0"><OuterReferences><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference></OuterReferences><RelOp NodeId="3" PhysicalOp="Clustered Index Scan" LogicalOp="Clustered Index Scan" EstimateRows="1" EstimatedRowsRead="1" EstimateIO="0.003125" EstimateCPU="0.0001581" AvgRowSize="11" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="0" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="1" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="1" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ForcedIndex="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference></DefinedValue></DefinedValues><Object Table="[@Target]" Index="[PK__#B4C8175__3213663B89F164C7]" Alias="[T]" Storage="RowStore"></Object></IndexScan></RelOp><RelOp NodeId="4" PhysicalOp="Clustered Index Seek" LogicalOp="Clustered Index Seek" EstimateRows="1" EstimatedRowsRead="1" EstimateIO="0.003125" EstimateCPU="0.0001581" AvgRowSize="15" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="0" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="2" Batches="0" ActualExecutionMode="Row" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="2" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualRowsRead="2" ActualEndOfScans="1" ActualExecutions="1"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Table="@Source" Alias="[S]" Column="c2"></ColumnReference></DefinedValue><DefinedValue><ColumnReference Table="@Source" Alias="[S]" Column="c3"></ColumnReference></DefinedValue></DefinedValues><Object Table="[@Source]" Index="[c]" Alias="[S]" Storage="RowStore"></Object><SeekPredicates><SeekPredicateNew><SeekKeys><Prefix ScanType="EQ"><RangeColumns><ColumnReference Table="@Source" Alias="[S]" Column="c1"></ColumnReference></RangeColumns><RangeExpressions><ScalarOperator ScalarString="@Target.[c1] as [T].[c1]"><Identifier><ColumnReference Table="@Target" Alias="[T]" Column="c1"></ColumnReference></Identifier></ScalarOperator></RangeExpressions></Prefix></SeekKeys></SeekPredicateNew></SeekPredicates></IndexScan></RelOp></NestedLoops></RelOp></StreamAggregate></RelOp></Update></RelOp></QueryPlan></StmtSimple></Statements></Batch></BatchSequence></ShowPlanXML> |
UPDATE T
SET T.c2 = S.c2,
T.c3 = S.c3
FROM @Target AS T
JOIN @Source AS S
ON S.c1 = T.c1
UPDATE
UPDATE
| Cached plan size | 32 KB |
|---|---|
| Estimated Operator Cost | 0 (0%) |
| Estimated Subtree Cost | 0.0165724 |
| Degree of Parallelism | 0 |
| Estimated Number of Rows | 1 |
Statement
UPDATE T
SET T.c2 = S.c2,
T.c3 = S.c3
FROM @Target AS T
JOIN @Source AS S
ON S.c1 = T.c1
Clustered Index Update
(Update)
Cost: 60%
Clustered Index Update
| Physical Operation | Clustered Index Update |
|---|---|
| Logical Operation | Update |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Number of Rows Read | 1 |
| Actual Number of Rows | 1 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.010001 (60%) |
| Estimated I/O Cost | 0.01 |
| Estimated CPU Cost | 0.000001 |
| Estimated Subtree Cost | 0.0165724 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 9 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 0 |
Object
[@Target].[PK__#B4C8175__3213663B89F164C7].[T]
Predicate
@Target.[c2] as [T].[c2] = RaiseIfNullUpdate(@Source.[c2] as [S].[c2]),@Target.[c3] as [T].[c3] = RaiseIfNullUpdate(@Source.[c3] as [S].[c3])
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 | 1 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.000001 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.000001 |
| Estimated Subtree Cost | 0.0065714 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 19 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 1 |
Output List
@Target.[T].c1
@Source.[S].c2
@Source.[S].c3
Nested Loops
(Inner 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 | Inner Join |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 2 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0000042 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000042 |
| Estimated Subtree Cost | 0.0065704 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 19 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 2 |
Output List
@Target.[T].c1
@Source.[S].c2
@Source.[S].c3
Outer References
@Target.[T].c1
Clustered Index Scan
[@Target].[PK__#B4C8175__3213663B89…
Cost: 20%
Clustered Index Scan
Scanning a clustered index, entirely or only a range.
| Physical Operation | Clustered Index Scan |
|---|---|
| Logical Operation | Clustered Index Scan |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 1 |
| Actual Number of Rows | 1 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032831 (20%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.0001581 |
| Estimated Subtree Cost | 0.0032831 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows to be Read | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 11 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 3 |
Output List
@Target.[T].c1
Object
[@Target].[PK__#B4C8175__3213663B89F164C7].[T]
Clustered Index Seek
[@Source].[c].[S]
Cost: 20%
Clustered Index Seek
Scanning a particular range of rows from a clustered index.
| Physical Operation | Clustered Index Seek |
|---|---|
| Logical Operation | Clustered Index Seek |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Storage | RowStore |
| Number of Rows Read | 2 |
| Actual Number of Rows | 2 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032831 (20%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.0001581 |
| Estimated Subtree Cost | 0.0032831 |
| Estimated Number of Executions | 1 |
| Number of Executions | 1 |
| Estimated Number of Rows to be Read | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 15 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 4 |
Output List
@Source.[S].c2
@Source.[S].c3
Object
[@Source].[c].[S]
Seek Predicates
Seek Keys[1]: Prefix: @Source.c1 = Scalar Operator(@Target.[c1] as [T].[c1])
| c1 | c2 | c3 |
|---|---|---|
| 1 | 2 | 3 |