com.netflix.iceberg.expressions

Class ResidualEvaluator

java.lang.Object

com.netflix.iceberg.expressions.ResidualEvaluator

All Implemented Interfaces:

java.io.Serializable

public class ResidualEvaluator
extends java.lang.Object
implements java.io.Serializable

Finds the residuals for an Expression the partitions in the given PartitionSpec.

A residual expression is made by partially evaluating an expression using partition values. For example, if a table is partitioned by day(utc_timestamp) and is read with a filter expression utc_timestamp >= a and utc_timestamp <= b, then there are 4 possible residuals expressions for the partition data, d:

• If d > day(a) and d < day(b), the residual is always true
• If d == day(a) and d != day(b), the residual is utc_timestamp >= a
• if d == day(b) and d != day(a), the residual is utc_timestamp <= b
• If d == day(a) == day(b), the residual is utc_timestamp >= a and utc_timestamp <= b

Partition data is passed using StructLike. Residuals are returned by residualFor(StructLike).

This class is thread-safe.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ResidualEvaluator(PartitionSpec spec, Expression expr)

Method Summary

Modifier and Type	Method and Description
Expression	residualFor(StructLike partitionData) Returns a residual expression for the given partition values.

Methods inherited from class java.lang.Object

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

Constructor Detail

ResidualEvaluator

public ResidualEvaluator(PartitionSpec spec,
                         Expression expr)

Method Detail

residualFor

public Expression residualFor(StructLike partitionData)

Returns a residual expression for the given partition values.

Parameters:

partitionData - partition data values

Returns:

the residual of this evaluator's expression from the partition values