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CREATE TABLE t (id int IDENTITY PRIMARY KEY);
SET STATISTICS XML ON;
SELECT *,
CASE WHEN EXISTS (SELECT 1
FROM t t2
WHERE t2.id = t1.id + 1) THEN 1 END
FROM t t1;
| id | (No column name) |
|---|
| 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 *,
 CASE WHEN EXISTS (SELECT 1
 FROM t t2
 WHERE t2.id = t1.id + 1) THEN 1 END
FROM t t1" StatementId="1" StatementCompId="1" StatementType="SELECT" StatementSqlHandle="0x09006317B5745DC7C91CF551005792D651BF0000000000000000000000000000000000000000000000000000" DatabaseContextSettingsId="1" ParentObjectId="0" StatementParameterizationType="0" RetrievedFromCache="true" StatementSubTreeCost="0.00657048" StatementEstRows="1" SecurityPolicyApplied="false" StatementOptmLevel="FULL" QueryHash="0x69CBFB793D8F8A03" QueryPlanHash="0x76FD3607A33554E9" 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="24" CompileTime="15" CompileCPU="0" CompileMemory="184"><MemoryGrantInfo SerialRequiredMemory="0" SerialDesiredMemory="0" GrantedMemory="0" MaxUsedMemory="0"></MemoryGrantInfo><OptimizerHardwareDependentProperties EstimatedAvailableMemoryGrant="1258238" EstimatedPagesCached="78639" EstimatedAvailableDegreeOfParallelism="1" MaxCompileMemory="2218408"></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="Compute Scalar" LogicalOp="Compute Scalar" EstimateRows="1" EstimateIO="0" EstimateCPU="1e-07" AvgRowSize="15" EstimatedTotalSubtreeCost="0.00657048" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference><ColumnReference Column="Expr1003"></ColumnReference></OutputList><ComputeScalar><DefinedValues><DefinedValue><ColumnReference Column="Expr1003"></ColumnReference><ScalarOperator ScalarString="CASE WHEN [Expr1004] THEN (1) ELSE NULL END"><IF><Condition><ScalarOperator><Identifier><ColumnReference Column="Expr1004"></ColumnReference></Identifier></ScalarOperator></Condition><Then><ScalarOperator><Const ConstValue="(1)"></Const></ScalarOperator></Then><Else><ScalarOperator><Const ConstValue="NULL"></Const></ScalarOperator></Else></IF></ScalarOperator></DefinedValue></DefinedValues><RelOp NodeId="1" PhysicalOp="Nested Loops" LogicalOp="Left Semi Join" EstimateRows="1" EstimateIO="0" EstimateCPU="4.18e-06" AvgRowSize="12" EstimatedTotalSubtreeCost="0.00657038" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference><ColumnReference Column="Expr1004"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="0" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><NestedLoops Optimized="0"><DefinedValues><DefinedValue><ColumnReference Column="Expr1004"></ColumnReference></DefinedValue></DefinedValues><OuterReferences><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference></OuterReferences><ProbeColumn><ColumnReference Column="Expr1004"></ColumnReference></ProbeColumn><RelOp NodeId="2" 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 Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="0" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualScans="1" ActualLogicalReads="0" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualEndOfScans="1" ActualExecutions="1" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="0" ForcedIndex="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues><DefinedValue><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference></DefinedValue></DefinedValues><Object Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Index="[PK__t__3213E83F1B75AA5E]" Alias="[t1]" IndexKind="Clustered" Storage="RowStore"></Object></IndexScan></RelOp><RelOp NodeId="3" PhysicalOp="Clustered Index Seek" LogicalOp="Clustered Index Seek" EstimateRows="1" EstimatedRowsRead="1" EstimateIO="0.003125" EstimateCPU="0.0001581" AvgRowSize="9" EstimatedTotalSubtreeCost="0.0032831" TableCardinality="0" Parallel="0" EstimateRebinds="0" EstimateRewinds="0" EstimatedExecutionMode="Row"><OutputList></OutputList><RunTimeInformation><RunTimeCountersPerThread Thread="0" ActualRows="0" Batches="0" ActualElapsedms="0" ActualCPUms="0" ActualScans="0" ActualLogicalReads="0" ActualPhysicalReads="0" ActualReadAheads="0" ActualLobLogicalReads="0" ActualLobPhysicalReads="0" ActualLobReadAheads="0" ActualEndOfScans="0" ActualExecutions="0" ActualExecutionMode="Row"></RunTimeCountersPerThread></RunTimeInformation><IndexScan Ordered="1" ScanDirection="FORWARD" ForcedIndex="0" ForceSeek="0" ForceScan="0" NoExpandHint="0" Storage="RowStore"><DefinedValues></DefinedValues><Object Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Index="[PK__t__3213E83F1B75AA5E]" Alias="[t2]" IndexKind="Clustered" Storage="RowStore"></Object><SeekPredicates><SeekPredicateNew><SeekKeys><Prefix ScanType="EQ"><RangeColumns><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t2]" Column="id"></ColumnReference></RangeColumns><RangeExpressions><ScalarOperator ScalarString="[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[id] as [t1].[id]+(1)"><Arithmetic Operation="ADD"><ScalarOperator><Identifier><ColumnReference Database="[fiddle_9f3d5cefc5cc466392fc566577617b10]" Schema="[dbo]" Table="[t]" Alias="[t1]" Column="id"></ColumnReference></Identifier></ScalarOperator><ScalarOperator><Const ConstValue="(1)"></Const></ScalarOperator></Arithmetic></ScalarOperator></RangeExpressions></Prefix></SeekKeys></SeekPredicateNew></SeekPredicates></IndexScan></RelOp></NestedLoops></RelOp></ComputeScalar></RelOp></QueryPlan></StmtSimple></Statements></Batch></BatchSequence></ShowPlanXML> |
SELECT *,
CASE WHEN EXISTS (SELECT 1
FROM t t2
WHERE t2.id = t1.id + 1) THEN 1 END
FROM t t1
SELECT
SELECT
| Cached plan size | 24 KB |
|---|---|
| Estimated Operator Cost | 0 (0%) |
| Estimated Subtree Cost | 0.0065705 |
| Degree of Parallelism | 0 |
| Estimated Number of Rows | 1 |
Statement
SELECT *,
CASE WHEN EXISTS (SELECT 1
FROM t t2
WHERE t2.id = t1.id + 1) THEN 1 END
FROM t t1
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 | 0.0000001 (0%) |
| Estimated I/O Cost | 0 |
| Estimated CPU Cost | 0.0000001 |
| Estimated Subtree Cost | 0.0065705 |
| Estimated Number of Executions | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 15 B |
| Node ID | 0 |
Output List
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[t1].id
Expr1003
Nested Loops
(Left Semi 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 Semi Join |
| Actual Execution Mode | Row |
| Estimated Execution Mode | Row |
| Actual Number of Rows | 0 |
| 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 | 12 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Node ID | 1 |
Output List
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[t1].id
Expr1004
Outer References
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[t1].id
Clustered Index Scan (Clustered)
[t].[PK__t__3213E83F1B75AA5E].[t1]
Cost: 50%
Clustered Index Scan (Clustered)
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 |
| Actual Number of Rows | 0 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032831 (50%) |
| 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 | False |
| Node ID | 2 |
Output List
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[t1].id
Object
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[PK__t__3213E83F1B75AA5E].[t1]
Clustered Index Seek (Clustered)
[t].[PK__t__3213E83F1B75AA5E].[t2]
Cost: 50%
Clustered Index Seek (Clustered)
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 |
| Actual Number of Rows | 0 |
| Actual Number of Batches | 0 |
| Estimated Operator Cost | 0.0032831 (50%) |
| Estimated I/O Cost | 0.003125 |
| Estimated CPU Cost | 0.0001581 |
| Estimated Subtree Cost | 0.0032831 |
| Estimated Number of Executions | 1 |
| Estimated Number of Rows to be Read | 1 |
| Estimated Number of Rows | 1 |
| Estimated Row Size | 9 B |
| Actual Rebinds | 0 |
| Actual Rewinds | 0 |
| Ordered | True |
| Node ID | 3 |
Object
[fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[PK__t__3213E83F1B75AA5E].[t2]
Seek Predicates
Seek Keys[1]: Prefix: [fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].id = Scalar Operator([fiddle_9f3d5cefc5cc466392fc566577617b10].[dbo].[t].[id] as [t1].[id]+(1))