org.apache.calcite.rex

Class RexFieldAccess

java.lang.Object

org.apache.calcite.rex.RexNode

org.apache.calcite.rex.RexFieldAccess

public class RexFieldAccess
extends RexNode

Access to a field of a row-expression.

You might expect to use a RexFieldAccess to access columns of relational tables, for example, the expression emp.empno in the query

SELECT emp.empno FROM emp

but there is a specialized expression RexInputRef for this purpose. So in practice, RexFieldAccess is usually used to access fields of correlating variables, for example the expression emp.deptno in

SELECT ename
 FROM dept
 WHERE EXISTS (
     SELECT NULL
     FROM emp
     WHERE emp.deptno = dept.deptno
     AND gender = 'F')

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.
RelDataTypeField	getField()
SqlKind	getKind() Returns the kind of node this is.
RexNode	getReferenceExpr() Returns the expression whose field is being accessed.
RelDataType	getType()

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

isA, isA, isAlwaysFalse, isAlwaysTrue, toString

Methods inherited from class java.lang.Object

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

Method Detail

getField

public RelDataTypeField getField()

getType

public RelDataType getType()

Specified by:

getType in class RexNode

getKind

public SqlKind getKind()

Description copied from class: RexNode

Returns the kind of node this is.

Overrides:

getKind in class RexNode

Returns:

Node kind, never null

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

getReferenceExpr

public RexNode getReferenceExpr()

Returns the expression whose field is being accessed.