Package org.apache.beam.sdk.schemas.transforms

Class Select.Flattened<T>

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<PCollection<T>,PCollection<Row>>

org.apache.beam.sdk.schemas.transforms.Select.Flattened<T>

All Implemented Interfaces:

Serializable, HasDisplayData

Enclosing class:

Select

public abstract static class Select.Flattened<T>
extends PTransform<PCollection<T>,PCollection<Row>>

A PTransform representing a flattened schema.

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.apache.beam.sdk.transforms.PTransform

annotations, displayData, name, resourceHints

Constructor Summary

Constructors

Constructor	Description
Flattened()

Method Summary

Modifier and Type	Method	Description
Select.Flattened<T>	concatFieldNames()	For nested fields, concatenate all the names separated by a _ character in the flattened schema.
PCollection<Row>	expand(PCollection<T> input)	Override this method to specify how this PTransform should be expanded on the given InputT.
Select.Flattened<T>	keepMostNestedFieldName()	For nested fields, keep just the most-nested field name.
Select.Flattened<T>	withFieldNameAs(String fieldName, String fieldRename)	Allows renaming a specific nested field.
Select.Flattened<T>	withOutputSchema(Schema schema)	Rename all output fields to match the specified schema.

Methods inherited from class org.apache.beam.sdk.transforms.PTransform

addAnnotation, compose, compose, getAdditionalInputs, getAnnotations, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, getResourceHints, populateDisplayData, setDisplayData, setResourceHints, toString, validate, validate

Methods inherited from class java.lang.Object

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

Constructor Details

Flattened

public Flattened()

Method Details

concatFieldNames

public Select.Flattened<T> concatFieldNames()

For nested fields, concatenate all the names separated by a _ character in the flattened schema.

keepMostNestedFieldName

public Select.Flattened<T> keepMostNestedFieldName()

For nested fields, keep just the most-nested field name. Will fail if this name is not unique.

withFieldNameAs

public Select.Flattened<T> withFieldNameAs(String fieldName,
 String fieldRename)

Allows renaming a specific nested field. Can be used if two fields resolve to the same name with the default name policies.

withOutputSchema

public Select.Flattened<T> withOutputSchema(Schema schema)

Rename all output fields to match the specified schema. If the specified schema is not compatible with the output schema a failure will be raised.

expand

public PCollection<Row> expand(PCollection<T> input)

Description copied from class: PTransform

Override this method to specify how this PTransform should be expanded on the given InputT.

NOTE: This method should not be called directly. Instead apply the PTransform should be applied to the InputT using the apply method.

Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).

Specified by:

expand in class PTransform<PCollection<T>,PCollection<Row>>