be.SIRAPRISE.ra

Class RelationalOperator

java.lang.Object

be.SIRAPRISE.ra.RelationalOperator

Direct Known Subclasses:

AGGREGATE, DIVIDEBYPER, EXTEND, GROUP, GTCLOSE, INTERSECT, INTERSECTUSING, JOIN, JOINUSING, LEFTJOIN, LEFTJOINUSING, MINUS, MINUSUSING, PACK, PROJECT, RENAME, RESTRICT, SEMIJOIN, SEMIJOINUSING, SEMIMINUS, SEMIMINUSUSING, SUMMARIZEBY, TCLOSE, TRANSFORM, UNGROUP, UNION, UNIONUSING, UNPACK, XMINUS, XMINUSUSING

public abstract class RelationalOperator
extends java.lang.Object

A Relational Operator is an operator that acts on Relation values and returns a Relation value

Author:

Erwin Smout

Constructor Summary

Constructors

Constructor and Description
RelationalOperator()

Method Summary

Modifier and Type	Method and Description
abstract int	getMaximumArgumentCount() Gets the maximum argument count for this operator.
abstract int	getMinimumArgumentCount() Gets the minimum argument count for this operator.
abstract java.lang.String	getName() Gets the operator name
abstract boolean	isMonoRelationOperator() Checks if the operator takes only one Relation as input
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RelationalOperator

public RelationalOperator()

Method Detail

getMaximumArgumentCount

public abstract int getMaximumArgumentCount()

Gets the maximum argument count for this operator. Note that stuff like rename lists are regarded as an argument as far as this count is concerned

Returns:

the maximum argument count for this operator.

getMinimumArgumentCount

public abstract int getMinimumArgumentCount()

Gets the minimum argument count for this operator. Note that stuff like rename lists are regarded as an argument as far as this count is concerned

Returns:

the minimum argument count for this operator

getName

public abstract java.lang.String getName()

Gets the operator name

Returns:

the operator name

isMonoRelationOperator

public abstract boolean isMonoRelationOperator()

Checks if the operator takes only one Relation as input

Returns:

true if the operator takes only one Relation as input

toString

public final java.lang.String toString()

Overrides:

toString in class java.lang.Object