edu.berkeley.cs186.database.query

Class JoinOperator

java.lang.Object

edu.berkeley.cs186.database.query.QueryOperator

edu.berkeley.cs186.database.query.JoinOperator

public class JoinOperator
extends QueryOperator

Nested Class Summary

Nested classes/interfaces inherited from class edu.berkeley.cs186.database.query.QueryOperator

QueryOperator.OperatorType

Constructor Summary

Constructors

Constructor and Description
JoinOperator(QueryOperator leftSource, QueryOperator rightSource, String leftColumnName, String rightColumnName) Create a join operator that pulls tuples from leftSource and rightSource.

Method Summary

Methods

Modifier and Type	Method and Description
Schema	computeSchema()
Iterator<Record>	execute() Joins tuples from leftSource and rightSource and returns an iterator of records.
QueryOperator	getLeftSource()
QueryOperator	getRightSource()
QueryOperator	getSource()
void	setLeftSource(QueryOperator leftSource)
void	setRightSource(QueryOperator rightSource)

Methods inherited from class edu.berkeley.cs186.database.query.QueryOperator

checkColumnNameEquality, checkSchemaForColumn, getDestination, getOutputSchema, getType, isGroupBy, isIndexScan, isJoin, isSelect, isSequentialScan, isWhere, setDestination, setOutputSchema, setSource

Methods inherited from class java.lang.Object

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

Constructor Detail

JoinOperator

public JoinOperator(QueryOperator leftSource,
            QueryOperator rightSource,
            String leftColumnName,
            String rightColumnName)
             throws QueryPlanException

Create a join operator that pulls tuples from leftSource and rightSource. Returns tuples for which leftColumnName and rightColumnName are equal.

Parameters:

leftSource - the left source operator

rightSource - the right source operator

leftColumnName - the column to join on from leftSource

rightColumnName - the column to join on from rightSource

Throws:

QueryPlanException

Method Detail

execute

public Iterator<Record> execute()
                         throws QueryPlanException,
                                DatabaseException

Joins tuples from leftSource and rightSource and returns an iterator of records.

Specified by:

execute in class QueryOperator

Returns:

an iterator of records

Throws:

QueryPlanException

DatabaseException

getSource

public QueryOperator getSource()
                        throws QueryPlanException

Overrides:

getSource in class QueryOperator

Throws:

QueryPlanException

getLeftSource

public QueryOperator getLeftSource()

getRightSource

public QueryOperator getRightSource()

setLeftSource

public void setLeftSource(QueryOperator leftSource)

setRightSource

public void setRightSource(QueryOperator rightSource)

computeSchema

public Schema computeSchema()
                     throws QueryPlanException

Specified by:

computeSchema in class QueryOperator

Throws:

QueryPlanException