Package org.rumbledb.runtime.flwor.clauses

Class JoinClauseIterator

java.lang.Object

org.rumbledb.runtime.plan.RuntimePlan<FlworTuple>

org.rumbledb.runtime.TupleRuntimePlan

org.rumbledb.runtime.flwor.clauses.JoinClauseIterator

All Implemented Interfaces:

Serializable, DataFrameRuntimePlan<FlworTuple>, LocalRuntimePlan<FlworTuple>, NativeQueryRuntimePlan

public class JoinClauseIterator
extends TupleRuntimePlan
implements DataFrameRuntimePlan<FlworTuple>

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.rumbledb.runtime.TupleRuntimePlan

child, evaluationDepthLimit, inputTupleProjection, outputTupleProjection

Fields inherited from class org.rumbledb.runtime.plan.RuntimePlan

staticContext

Constructor Summary

Constructors

Constructor	Description
JoinClauseIterator(TupleRuntimePlan leftChild, TupleRuntimePlan rightChild, boolean isLeftOuterJoin, RuntimeStaticContext staticContext)

Method Summary

Modifier and Type	Method	Description
boolean	containsClause(FLWOR_CLAUSES kind)	Says whether or not the clause and its descendants include a clause of the specified kind.
Cursor<FlworTuple>	createNativeCursor(DynamicContext context)	Creates an independent cursor for one native local evaluation.
FlworDataFrame	createNativeDataFrame(DynamicContext context)	Builds the DataFrame for one evaluation.
protected Map<Name,DynamicContext.VariableDependency>	getInputTupleVariableDependencies(Map<Name,DynamicContext.VariableDependency> parentProjection)	Builds the DataFrame projection that this clause needs to receive from its child clause.
boolean	isSparkJobNeeded()	Says whether this expression evaluation triggers a Spark job.
static FlworDataFrame	joinInputTupleWithSequenceOnPredicate(DynamicContext context, org.apache.spark.sql.Dataset<org.apache.spark.sql.Row> leftInputTuple, org.apache.spark.sql.Dataset<org.apache.spark.sql.Row> rightInputTuple, Map<Name,DynamicContext.VariableDependency> outputTupleVariableDependencies, List<Name> variablesInLeftInputTuple, List<Name> variablesInRightInputTuple, ItemRuntimePlan predicateIterator, boolean isLeftOuterJoin, Name newRightSideVariableName, ExceptionMetadata metadata, RuntimeStaticContext staticContext)	Joins two input tuples.

Methods inherited from class org.rumbledb.runtime.TupleRuntimePlan

canSetEvaluationDepthLimit, generateNativeQuery, getChildIterator, getDynamicContextVariableDependencies, getEvaluationDepthLimit, getHeight, getOutputTupleVariableNames, getStaticContext, getSubtreeBeyondLimit, isDataFrame, print, setEvaluationDepthLimit, setInputAndOutputTupleVariableDependencies, toString

Methods inherited from class org.rumbledb.runtime.plan.RuntimePlan

getConfiguration, getCursor, getDataFrame, getMetadata, getRDD, getRuntimeStaticContext, materialize, materializeAtMost, materializeAtMostOne, materializeExactlyOne, materializeFirstOrNull

Methods inherited from class java.lang.Object

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

Constructor Details

JoinClauseIterator

public JoinClauseIterator(TupleRuntimePlan leftChild,
 TupleRuntimePlan rightChild,
 boolean isLeftOuterJoin,
 RuntimeStaticContext staticContext)

Method Details

createNativeCursor

public Cursor<FlworTuple> createNativeCursor(DynamicContext context)

Description copied from interface: LocalRuntimePlan

Creates an independent cursor for one native local evaluation.

Specified by:

createNativeCursor in interface LocalRuntimePlan<FlworTuple>

Specified by:

createNativeCursor in class TupleRuntimePlan

Parameters:

context - the dynamic context for that evaluation

Returns:

an unopened cursor

joinInputTupleWithSequenceOnPredicate

public static FlworDataFrame joinInputTupleWithSequenceOnPredicate(DynamicContext context,
 org.apache.spark.sql.Dataset<org.apache.spark.sql.Row> leftInputTuple,
 org.apache.spark.sql.Dataset<org.apache.spark.sql.Row> rightInputTuple,
 Map<Name,DynamicContext.VariableDependency> outputTupleVariableDependencies,
 List<Name> variablesInLeftInputTuple,
 List<Name> variablesInRightInputTuple,
 ItemRuntimePlan predicateIterator,
 boolean isLeftOuterJoin,
 Name newRightSideVariableName,
 ExceptionMetadata metadata,
 RuntimeStaticContext staticContext)

Joins two input tuples. Warning: if the two tuples collide in their columns, unexpected things may happen for now.

Parameters:

context - the dynamic context for the evaluation of the predicate expression.

leftInputTuple - the left tuple.

rightInputTuple - the right tuple.

outputTupleVariableDependencies - the necessary and sufficient variable dependencies that the output tuple should contain.

variablesInLeftInputTuple - a list of the variables in the left tuple.

variablesInRightInputTuple - a list of the variables in the right tuple.

predicateIterator - the predicate iterator.

isLeftOuterJoin - true if it is a left outer join, false otherwise.

newRightSideVariableName - the new name of the variable to rename the context item in the output (null if no rename).

metadata - the metadata.

Returns:

the joined tuple.

createNativeDataFrame

public FlworDataFrame createNativeDataFrame(DynamicContext context)

Description copied from interface: DataFrameRuntimePlan

Builds the DataFrame for one evaluation.

Specified by:

createNativeDataFrame in interface DataFrameRuntimePlan<FlworTuple>

Parameters:

context - the dynamic context for that evaluation

Returns:

the resulting DataFrame

getInputTupleVariableDependencies

protected Map<Name,DynamicContext.VariableDependency> getInputTupleVariableDependencies(Map<Name,DynamicContext.VariableDependency> parentProjection)

Description copied from class: TupleRuntimePlan

Builds the DataFrame projection that this clause needs to receive from its child clause. The intent is that the result of this method is forwarded to the child clause in getDataFrame() so it can optimize some values away. Invariant: all keys in getInputTupleVariableDependencies(...) MUST be output tuple variables, i.e., appear in this.child.getOutputTupleVariableNames()

Specified by:

getInputTupleVariableDependencies in class TupleRuntimePlan

Parameters:

parentProjection - the projection needed by the parent clause.

Returns:

the projection needed by this clause.

containsClause

public boolean containsClause(FLWOR_CLAUSES kind)

Description copied from class: TupleRuntimePlan

Says whether or not the clause and its descendants include a clause of the specified kind.

Specified by:

containsClause in class TupleRuntimePlan

Parameters:

kind - the kind of clause to test for.

Returns:

true if there is one. False otherwise.

isSparkJobNeeded

public boolean isSparkJobNeeded()

Says whether this expression evaluation triggers a Spark job.

Specified by:

isSparkJobNeeded in class TupleRuntimePlan

Returns:

true if the execution triggers a Spark, false otherwise, null if undetermined yet.