org.apache.gravitino.rel.expressions.transforms

Interface Transform

All Superinterfaces:

Expression

All Known Subinterfaces:

Partitioning

All Known Implementing Classes:

BucketPartitioningDTO, DayPartitioningDTO, FunctionPartitioningDTO, HourPartitioningDTO, IdentityPartitioningDTO, ListPartitioningDTO, MonthPartitioningDTO, Partitioning.SingleFieldPartitioning, RangePartitioningDTO, Transform.SingleFieldTransform, Transforms.ApplyTransform, Transforms.BucketTransform, Transforms.DayTransform, Transforms.HourTransform, Transforms.IdentityTransform, Transforms.ListTransform, Transforms.MonthTransform, Transforms.RangeTransform, Transforms.TruncateTransform, Transforms.YearTransform, TruncatePartitioningDTO, YearPartitioningDTO

@Evolving
public interface Transform
extends Expression

Represents a transform function in the public logical expression API.

For example, the transform date(ts) is used to derive a date value from a timestamp column. The transform name is "date" and its argument is a reference to the "ts" column.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	Transform.SingleFieldTransform Base class for simple transforms of a single field.

Field Summary

Fields inherited from interface org.apache.gravitino.rel.expressions.Expression

EMPTY_EXPRESSION, EMPTY_NAMED_REFERENCE

Method Summary

Modifier and Type	Method and Description
Expression[]	arguments()
default Partition[]	assignments()
default Expression[]	children()
java.lang.String	name()

Methods inherited from interface org.apache.gravitino.rel.expressions.Expression

references

Method Detail

name

java.lang.String name()

Returns:

The transform function name.

arguments

Expression[] arguments()

Returns:

The arguments passed to the transform function.

assignments

default Partition[] assignments()

Returns:

The preassigned partitions in the partitioning. Currently, only Transforms.ListTransform and Transforms.RangeTransform need to deal with assignments

children

default Expression[] children()

Specified by:

children in interface Expression

Returns:

An array of the children of this node. Children should not change.