org.apache.beam.sdk.extensions.sql

Class QueryTransform

java.lang.Object

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

org.apache.beam.sdk.extensions.sql.QueryTransform

All Implemented Interfaces:

java.io.Serializable, HasDisplayData

public abstract class QueryTransform
extends PTransform<PInput,PCollection<Row>>

A PTransform representing an execution plan for a SQL query.

The table names in the input PCollectionTuple are only valid during the current query.

See Also:

Serialized Form

Field Summary

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

name

Constructor Summary

Constructors

Constructor and Description
QueryTransform()

Method Summary

Modifier and Type	Method and Description
PCollection<Row>	expand(PInput input) Override this method to specify how this PTransform should be expanded on the given InputT.
QueryTransform	registerUdaf(java.lang.String functionName, Combine.CombineFn combineFn) register a Combine.CombineFn as UDAF function used in this query.
QueryTransform	registerUdf(java.lang.String functionName, java.lang.Class<? extends BeamSqlUdf> clazz) register a UDF function used in this query.
QueryTransform	registerUdf(java.lang.String functionName, SerializableFunction sfn) Register SerializableFunction as a UDF function used in this query.
static QueryTransform	withQueryString(java.lang.String queryString) Creates a QueryTransform with SQL queryString.

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

getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validate

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryTransform

public QueryTransform()

Method Detail

expand

public PCollection<Row> expand(PInput 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<PInput,PCollection<Row>>

withQueryString

public static QueryTransform withQueryString(java.lang.String queryString)

Creates a QueryTransform with SQL queryString.

registerUdf

public QueryTransform registerUdf(java.lang.String functionName,
                                  java.lang.Class<? extends BeamSqlUdf> clazz)

register a UDF function used in this query.

Refer to BeamSqlUdf for more about how to implement a UDF in BeamSql.

registerUdf

public QueryTransform registerUdf(java.lang.String functionName,
                                  SerializableFunction sfn)

Register SerializableFunction as a UDF function used in this query. Note, SerializableFunction must have a constructor without arguments.

registerUdaf

public QueryTransform registerUdaf(java.lang.String functionName,
                                   Combine.CombineFn combineFn)

register a Combine.CombineFn as UDAF function used in this query.