org.apache.iceberg.expressions

Class Projections

java.lang.Object

org.apache.iceberg.expressions.Projections

public class Projections
extends java.lang.Object

Utils to project expressions on rows to expressions on partitions.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Projections.ProjectionEvaluator A class that projects expressions for a table's data rows into expressions on the table's partition values, for a table's partition spec.

Method Summary

Modifier and Type	Method and Description
static Projections.ProjectionEvaluator	inclusive(PartitionSpec spec) Creates an inclusive ProjectionEvaluator for the spec, defaulting to case sensitive mode.
static Projections.ProjectionEvaluator	inclusive(PartitionSpec spec, boolean caseSensitive) Creates an inclusive ProjectionEvaluator for the spec.
static Projections.ProjectionEvaluator	strict(PartitionSpec spec) Creates a strict ProjectionEvaluator for the spec, defaulting to case sensitive mode.
static Projections.ProjectionEvaluator	strict(PartitionSpec spec, boolean caseSensitive) Creates a strict ProjectionEvaluator for the spec.

Methods inherited from class java.lang.Object

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

Method Detail

inclusive

public static Projections.ProjectionEvaluator inclusive(PartitionSpec spec)

Creates an inclusive ProjectionEvaluator for the spec, defaulting to case sensitive mode.

An evaluator is used to project expressions for a table's data rows into expressions on the table's partition values. The evaluator returned by this function is inclusive and will build expressions with the following guarantee: if the original expression matches a row, then the projected expression will match that row's partition.

Each predicate in the expression is projected using Transform.project(String, BoundPredicate).

Parameters:

spec - a partition spec

Returns:

an inclusive projection evaluator for the partition spec

See Also:

Inclusive transform used for each predicate

inclusive

public static Projections.ProjectionEvaluator inclusive(PartitionSpec spec,
                                                        boolean caseSensitive)

Creates an inclusive ProjectionEvaluator for the spec.

An evaluator is used to project expressions for a table's data rows into expressions on the table's partition values. The evaluator returned by this function is inclusive and will build expressions with the following guarantee: if the original expression matches a row, then the projected expression will match that row's partition.

Each predicate in the expression is projected using Transform.project(String, BoundPredicate).

Parameters:

spec - a partition spec

caseSensitive - whether the Projection should consider case sensitivity on column names or not.

Returns:

an inclusive projection evaluator for the partition spec

See Also:

Inclusive transform used for each predicate

strict

public static Projections.ProjectionEvaluator strict(PartitionSpec spec)

Creates a strict ProjectionEvaluator for the spec, defaulting to case sensitive mode.

An evaluator is used to project expressions for a table's data rows into expressions on the table's partition values. The evaluator returned by this function is strict and will build expressions with the following guarantee: if the projected expression matches a partition, then the original expression will match all rows in that partition.

Each predicate in the expression is projected using Transform.projectStrict(String, BoundPredicate).

Parameters:

spec - a partition spec

Returns:

a strict projection evaluator for the partition spec

See Also:

Strict transform used for each predicate

strict

public static Projections.ProjectionEvaluator strict(PartitionSpec spec,
                                                     boolean caseSensitive)

Creates a strict ProjectionEvaluator for the spec.

An evaluator is used to project expressions for a table's data rows into expressions on the table's partition values. The evaluator returned by this function is strict and will build expressions with the following guarantee: if the projected expression matches a partition, then the original expression will match all rows in that partition.

Each predicate in the expression is projected using Transform.projectStrict(String, BoundPredicate).

Parameters:

spec - a partition spec

caseSensitive - whether the Projection should consider case sensitivity on column names or not.

Returns:

a strict projection evaluator for the partition spec

See Also:

Strict transform used for each predicate