org.apache.spark.sql.sources.v2

Interface WriteSupport

All Superinterfaces:

DataSourceV2

@InterfaceStability.Evolving
public interface WriteSupport
extends DataSourceV2

A mix-in interface for DataSourceV2. Data sources can implement this interface to provide data writing ability and save the data to the data source.

Method Summary

Modifier and Type	Method and Description
java.util.Optional<DataSourceWriter>	createWriter(String writeUUID, StructType schema, SaveMode mode, DataSourceOptions options) Creates an optional DataSourceWriter to save the data to this data source.

Method Detail

createWriter

java.util.Optional<DataSourceWriter> createWriter(String writeUUID,
                                                  StructType schema,
                                                  SaveMode mode,
                                                  DataSourceOptions options)

Creates an optional DataSourceWriter to save the data to this data source. Data sources can return None if there is no writing needed to be done according to the save mode. If this method fails (by throwing an exception), the action will fail and no Spark job will be submitted.

Parameters:

writeUUID - A unique string for the writing job. It's possible that there are many writing jobs running at the same time, and the returned DataSourceWriter can use this job id to distinguish itself from other jobs.

schema - the schema of the data to be written.

mode - the save mode which determines what to do when the data are already in this data source, please refer to SaveMode for more details.

options - the options for the returned data source writer, which is an immutable case-insensitive string-to-string map.

Returns:

a writer to append data to this data source