ResidualEvaluator

java.lang.Object
- org.apache.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

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static ResidualEvaluator`	`of(PartitionSpec spec, Expression expr, boolean caseSensitive)`	Return a residual evaluator for a `spec` and `expression`.
`Expression`	`residualFor(StructLike partitionData)`	Returns a residual expression for the given partition values.
`static ResidualEvaluator`	`unpartitioned(Expression expr)`	Return a residual evaluator for an unpartitioned `spec`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - unpartitioned
```
public static ResidualEvaluator unpartitioned(Expression expr)
```
    Return a residual evaluator for an unpartitioned spec.
    
    Parameters:
    
    expr - an expression
    
    Returns:
    
    a residual evaluator that always returns the expression
  - of
```
public static ResidualEvaluator of(PartitionSpec spec,
                                   Expression expr,
                                   boolean caseSensitive)
```
    Return a residual evaluator for a spec and expression.
    
    Parameters:
    
    spec - a partition spec
    
    expr - an expression
    
    Returns:
    
    a residual evaluator for the expression
  - 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