org.apache.calcite.rex

Class RexOver

java.lang.Object

org.apache.calcite.rex.RexNode

org.apache.calcite.rex.RexCall

org.apache.calcite.rex.RexOver

public class RexOver
extends RexCall

Call to an aggregate function over a window.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	RexOver.Finder Visitor which detects a RexOver inside a RexNode expression.
private static class	RexOver.OverFound Exception thrown when an OVER is found.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	distinct
private static RexOver.Finder	FINDER
private RexWindow	window

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

op, operands, type

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

digest

Constructor Summary

Constructors

Constructor and Description
RexOver(RelDataType type, SqlAggFunction op, List<RexNode> operands, RexWindow window, boolean distinct) Creates a RexOver.

Method Summary

Modifier and Type	Method and 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.
RexCall	clone(RelDataType type, List<RexNode> operands) Creates a new call to the same operator with different operands.
protected String	computeDigest(boolean withType)
static boolean	containsOver(List<RexNode> exprs, RexNode condition) Returns whether an expression list contains an OVER clause.
static boolean	containsOver(RexNode expr) Returns whether an expression contains an OVER clause.
static boolean	containsOver(RexProgram program) Returns whether a program contains an OVER clause.
SqlAggFunction	getAggOperator() Returns the aggregate operator for this expression.
RexWindow	getWindow()
boolean	isDistinct()

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

getKind, getOperands, getOperator, getType, isAlwaysFalse, isAlwaysTrue, toString

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

isA, isA

Methods inherited from class java.lang.Object

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

Field Detail

FINDER

private static final RexOver.Finder FINDER

window

private final RexWindow window

distinct

private final boolean distinct

Constructor Detail

RexOver

RexOver(RelDataType type,
        SqlAggFunction op,
        List<RexNode> operands,
        RexWindow window,
        boolean distinct)

Creates a RexOver.

For example, "SUM(DISTINCT x) OVER (ROWS 3 PRECEDING)" is represented as:

• type = Integer,
• op = SqlStdOperatorTable.SUM,
• operands = { RexFieldAccess("x") }
• window = SqlWindow(ROWS 3 PRECEDING)

Parameters:

type - Result type

op - Aggregate operator

operands - Operands list

window - Window specification

distinct - Aggregate operator is applied on distinct elements

Method Detail

getAggOperator

public SqlAggFunction getAggOperator()

Returns the aggregate operator for this expression.

getWindow

public RexWindow getWindow()

isDistinct

public boolean isDistinct()

computeDigest

protected String computeDigest(boolean withType)

Overrides:

computeDigest in class RexCall

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.

Overrides:

accept in class RexCall

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.

Overrides:

accept in class RexCall

containsOver

public static boolean containsOver(RexNode expr)

Returns whether an expression contains an OVER clause.

containsOver

public static boolean containsOver(RexProgram program)

Returns whether a program contains an OVER clause.

containsOver

public static boolean containsOver(List<RexNode> exprs,
                                   RexNode condition)

Returns whether an expression list contains an OVER clause.

clone

public RexCall clone(RelDataType type,
                     List<RexNode> operands)

Description copied from class: RexCall

Creates a new call to the same operator with different operands.

Overrides:

clone in class RexCall

Parameters:

type - Return type

operands - Operands to call

Returns:

New call