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

digest

Method Summary

Methods

Modifier and Type	Method and Description
<R> R	accept(RexVisitor<R> visitor) Accepts a visitor, dispatching to the right overloaded visitXxx method.
int	getOffset()
RelDataType	getType()

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

getKind, isA, isA, isAlwaysFalse, isAlwaysTrue, toString

Methods inherited from class java.lang.Object

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

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