org.apache.flink.table.sources

Interface TableSource<T>

Type Parameters:

T - The return type of the TableSource.

All Known Subinterfaces:

BatchTableSource<T>, LookupableTableSource<T>, StreamTableSource<T>

All Known Implementing Classes:

BatchSQLTestProgram.GeneratorTableSource, BoundedTransactionTableSource, CsvTableSource, HBaseTableSource, HiveTableSource, InputFormatTableSource, JDBCTableSource, Kafka010TableSource, Kafka011TableSource, Kafka08TableSource, Kafka09TableSource, KafkaTableSource, KafkaTableSourceBase, OrcTableSource, ParquetTableSource, StreamSQLTestProgram.GeneratorTableSource, UnboundedTransactionTableSource

@PublicEvolving
public interface TableSource<T>

Defines an external table with the schema that is provided by getTableSchema().

The data of a TableSource is produced as a DataSet in case of a BatchTableSource or as a DataStream in case of a StreamTableSource. The type of ths produced DataSet or DataStream is specified by the getProducedDataType() method.

By default, the fields of the TableSchema are implicitly mapped by name to the fields of the produced DataType. An explicit mapping can be defined by implementing the DefinedFieldMapping interface.

Method Summary

Modifier and Type	Method and Description
default String	explainSource() Describes the table source.
default DataType	getProducedDataType() Returns the DataType for the produced data of the TableSource.
default TypeInformation<T>	getReturnType() Deprecated. This method will be removed in future versions as it uses the old type system. It is recommended to use getProducedDataType() instead which uses the new type system based on DataTypes. Please make sure to use either the old or the new type system consistently to avoid unintended behavior. See the website documentation for more information.
TableSchema	getTableSchema() Deprecated. Table schema is a logical description of a table and should not be part of the physical TableSource. Define schema when registering a Table either in DDL or in TableEnvironment#connect(...).

Method Detail

getProducedDataType

default DataType getProducedDataType()

Returns the DataType for the produced data of the TableSource.

Returns:

The data type of the returned DataSet or DataStream.

getReturnType

@Deprecated
default TypeInformation<T> getReturnType()

Deprecated. This method will be removed in future versions as it uses the old type system. It is recommended to use getProducedDataType() instead which uses the new type system based on DataTypes. Please make sure to use either the old or the new type system consistently to avoid unintended behavior. See the website documentation for more information.

getTableSchema

@Deprecated
TableSchema getTableSchema()

Deprecated. Table schema is a logical description of a table and should not be part of the physical TableSource. Define schema when registering a Table either in DDL or in TableEnvironment#connect(...).

Returns the schema of the produced table.

Returns:

The TableSchema of the produced table.

explainSource

default String explainSource()

Describes the table source.

Returns:

A String explaining the TableSource.