Package org.apache.calcite.adapter.csv

Class CsvTableScan

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.core.TableScan

org.apache.calcite.adapter.csv.CsvTableScan

All Implemented Interfaces:

java.lang.Cloneable, EnumerableRel, RelOptNode, RelNode

public class CsvTableScan
extends TableScan
implements EnumerableRel

Relational expression representing a scan of a CSV file.

Like any table scan, it serves as a leaf node of a query tree.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.calcite.adapter.enumerable.EnumerableRel

EnumerableRel.Prefer, EnumerableRel.Result

Nested classes/interfaces inherited from interface org.apache.calcite.rel.RelNode

RelNode.Context

Field Summary

Fields

Modifier and Type	Field	Description
(package private) CsvTranslatableTable	csvTable
(package private) int[]	fields

Fields inherited from class org.apache.calcite.rel.core.TableScan

table

Fields inherited from class org.apache.calcite.rel.AbstractRelNode

digest, id, rowType, traitSet

Fields inherited from interface org.apache.calcite.adapter.enumerable.EnumerableRel

FILTER_FACTORY, PROJECT_FACTORY

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CsvTableScan(RelOptCluster cluster, RelOptTable table, CsvTranslatableTable csvTable, int[] fields)

Method Summary

Modifier and Type	Method	Description
RelOptCost	computeSelfCost(RelOptPlanner planner, RelMetadataQuery mq)	Returns the cost of this plan (not including children).
RelNode	copy(RelTraitSet traitSet, java.util.List<RelNode> inputs)	Creates a copy of this relational expression, perhaps changing traits and inputs.
RelDataType	deriveRowType()
RelWriter	explainTerms(RelWriter pw)	Describes the inputs and attributes of this relational expression.
EnumerableRel.Result	implement(EnumerableRelImplementor implementor, EnumerableRel.Prefer pref)	Creates a plan for this expression according to a calling convention.
void	register(RelOptPlanner planner)	Registers any special rules specific to this kind of relational expression.

Methods inherited from class org.apache.calcite.rel.core.TableScan

accept, estimateRowCount, getCollationList, getTable, identity, identity, project

Methods inherited from class org.apache.calcite.rel.AbstractRelNode

accept, childrenAccept, collectVariablesSet, collectVariablesUsed, computeDigest, computeSelfCost, explain, getChildExps, getCluster, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getInputs, getQuery, getRelTypeName, getRows, getRowType, getTraitSet, getVariablesSet, getVariablesStopped, isDistinct, isKey, isValid, isValid, metadata, onRegister, recomputeDigest, replaceInput, sole, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.calcite.rel.RelNode

accept, accept, childrenAccept, collectVariablesSet, collectVariablesUsed, computeSelfCost, estimateRowCount, explain, getChildExps, getCollationList, getConvention, getCorrelVariable, getExpectedInputRowType, getInput, getInputs, getQuery, getRelTypeName, getRows, getRowType, getTable, getVariablesSet, getVariablesStopped, isDistinct, isKey, isValid, isValid, metadata, onRegister, recomputeDigest, replaceInput

Methods inherited from interface org.apache.calcite.plan.RelOptNode

getCluster, getDescription, getDigest, getId, getTraitSet

Field Detail

csvTable

final CsvTranslatableTable csvTable

fields

final int[] fields

Constructor Detail

CsvTableScan

protected CsvTableScan(RelOptCluster cluster,
                       RelOptTable table,
                       CsvTranslatableTable csvTable,
                       int[] fields)

Method Detail

copy

public RelNode copy(RelTraitSet traitSet,
                    java.util.List<RelNode> inputs)

Description copied from interface: RelNode

Creates a copy of this relational expression, perhaps changing traits and inputs.

Sub-classes with other important attributes are encouraged to create variants of this method with more parameters.

Specified by:

copy in interface RelNode

Overrides:

copy in class AbstractRelNode

Parameters:

traitSet - Trait set

inputs - Inputs

Returns:

Copy of this relational expression, substituting traits and inputs

explainTerms

public RelWriter explainTerms(RelWriter pw)

Description copied from class: AbstractRelNode

Describes the inputs and attributes of this relational expression. Each node should call super.explainTerms, then call the RelWriterImpl.input(String, RelNode) and RelWriterImpl.item(String, Object) methods for each input and attribute.

Overrides:

explainTerms in class TableScan

Parameters:

pw - Plan writer

Returns:

Plan writer for fluent-explain pattern

deriveRowType

public RelDataType deriveRowType()

Overrides:

deriveRowType in class TableScan

register

public void register(RelOptPlanner planner)

Description copied from interface: RelNode

Registers any special rules specific to this kind of relational expression.

The planner calls this method this first time that it sees a relational expression of this class. The derived class should call RelOptPlanner.addRule(org.apache.calcite.plan.RelOptRule) for each rule, and then call super.register.

Specified by:

register in interface RelNode

Overrides:

register in class AbstractRelNode

Parameters:

planner - Planner to be used to register additional relational expressions

computeSelfCost

public RelOptCost computeSelfCost(RelOptPlanner planner,
                                  RelMetadataQuery mq)

Description copied from interface: RelNode

Returns the cost of this plan (not including children). The base implementation throws an error; derived classes should override.

NOTE jvs 29-Mar-2006: Don't call this method directly. Instead, use RelMetadataQuery.getNonCumulativeCost(org.apache.calcite.rel.RelNode), which gives plugins a chance to override the rel's default ideas about cost.

Specified by:

computeSelfCost in interface RelNode

Overrides:

computeSelfCost in class TableScan

Parameters:

planner - Planner for cost calculation

mq - Metadata query

Returns:

Cost of this plan (not including children)

implement

public EnumerableRel.Result implement(EnumerableRelImplementor implementor,
                                      EnumerableRel.Prefer pref)

Description copied from interface: EnumerableRel

Creates a plan for this expression according to a calling convention.

Specified by:

implement in interface EnumerableRel

Parameters:

implementor - Implementor

pref - Preferred representation for rows in result expression

Returns:

Plan for this expression according to a calling convention