org.apache.tajo.plan.logical

Class RelationNode

java.lang.Object

org.apache.tajo.plan.logical.LogicalNode

org.apache.tajo.plan.logical.RelationNode

All Implemented Interfaces:

Cloneable, GsonObject

Direct Known Subclasses:

ScanNode, TableSubQueryNode

public abstract class RelationNode
extends LogicalNode

It provides a logical view of a relation. Regarding a table, the main difference between a logical view and a physical view is as follows:

• In logical view, each column in the table has qualified name by table alias name. In addition, the schema of logical view will includes partition columns if we use column-partitioned tables.
• In contrast, in physical view: each column in the table has qualified name by the original table.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RelationNode(int pid, NodeType nodeType)

Method Summary

Methods

Modifier and Type	Method and Description
abstract String	getAlias()
abstract String	getCanonicalName()
abstract Schema	getLogicalSchema()
abstract String	getTableName()
abstract boolean	hasAlias()

Methods inherited from class org.apache.tajo.plan.logical.LogicalNode

childNum, clone, deepEquals, equals, getChild, getCost, getInSchema, getOutSchema, getPID, getPlanString, getType, postOrder, preOrder, setCost, setInSchema, setOutSchema, setPID, setType, toJson, toString

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RelationNode

protected RelationNode(int pid,
            NodeType nodeType)

Method Detail

hasAlias

public abstract boolean hasAlias()

getAlias

public abstract String getAlias()

getTableName

public abstract String getTableName()

getCanonicalName

public abstract String getCanonicalName()

getLogicalSchema

public abstract Schema getLogicalSchema()