Package org.apache.calcite.rex

Class RexRangeRef

java.lang.Object

org.apache.calcite.rex.RexNode

org.apache.calcite.rex.RexRangeRef

public class RexRangeRef
extends RexNode

Reference to a range of columns.

This construct is used only during the process of translating a SQL tree to a rel/rex tree. Regular rex trees do not contain this construct.

While translating a join of EMP(EMPNO, ENAME, DEPTNO) to DEPT(DEPTNO2, DNAME) we create RexRangeRef(DeptType,3) to represent the pair of columns (DEPTNO2, DNAME) which came from DEPT. The type has 2 columns, and therefore the range represents columns {3, 4} of the input.

Suppose we later create a reference to the DNAME field of this RexRangeRef; it will return a RexInputRef(5,Integer), and the RexRangeRef will disappear.

Field Summary

Fields

Modifier and Type	Field	Description
private int	offset
private RelDataType	type

Fields inherited from class org.apache.calcite.rex.RexNode

digest

Constructor Summary

Constructors

Constructor	Description
RexRangeRef(RelDataType rangeType, int offset)	Creates a range reference.

Method Summary

Modifier and Type	Method	Description
<R,P> R	accept(RexBiVisitor<R,P> visitor, P arg)	Accepts a visitor with a payload, dispatching to the right overloaded RexBiVisitor.visitInputRef(RexInputRef, Object) visitXxx} method.
<R> R	accept(RexVisitor<R> visitor)	Accepts a visitor, dispatching to the right overloaded visitXxx method.
boolean	equals(java.lang.Object obj)
int	getOffset()
RelDataType	getType()
int	hashCode()

Methods inherited from class org.apache.calcite.rex.RexNode

getKind, isA, isA, isAlwaysFalse, isAlwaysTrue, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

type

private final RelDataType type

offset

private final int offset

Constructor Detail

RexRangeRef

RexRangeRef(RelDataType rangeType,
            int offset)

Creates a range reference.

Parameters:

rangeType - Type of the record returned

offset - Offset of the first column within the input record

Method Detail

getType

public RelDataType getType()

Specified by:

getType in class RexNode

getOffset

public int getOffset()

accept

public <R> R accept(RexVisitor<R> visitor)

Description copied from class: RexNode

Accepts a visitor, dispatching to the right overloaded visitXxx method.

Also see RexUtil.apply(RexVisitor, java.util.List, RexNode), which applies a visitor to several expressions simultaneously.

Specified by:

accept in class RexNode

accept

public <R,P> R accept(RexBiVisitor<R,P> visitor,
                            P arg)

Description copied from class: RexNode

Accepts a visitor with a payload, dispatching to the right overloaded RexBiVisitor.visitInputRef(RexInputRef, Object) visitXxx} method.

Specified by:

accept in class RexNode

equals

public boolean equals(java.lang.Object obj)

Description copied from class: RexNode

Every node must implement RexNode.equals(java.lang.Object) based on its content

Specified by:

equals in class RexNode

hashCode

public int hashCode()

Description copied from class: RexNode

Every node must implement RexNode.hashCode() consistent with RexNode.equals(java.lang.Object)

Specified by:

hashCode in class RexNode