org.apache.flink.table.sinks

Interface UpsertStreamTableSink<T>

Type Parameters:

T - Type of records that this TableSink expects and supports.

All Superinterfaces:

StreamTableSink<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>>, org.apache.flink.table.sinks.TableSink<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>>

@PublicEvolving
public interface UpsertStreamTableSink<T>
extends StreamTableSink<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>>

Defines an external TableSink to emit a streaming Table with insert, update, and delete changes. The Table must be have unique key fields (atomic or composite) or be append-only.

If the Table does not have a unique key and is not append-only, a TableException will be thrown.

The unique key of the table is configured by the setKeyFields(String[]) method.

The Table will be converted into a stream of upsert and delete messages which are encoded as Tuple2. The first field is a Boolean flag to indicate the message type. The second field holds the record of the requested type T.

A message with true Boolean field is an upsert message for the configured key.

A message with false flag is a delete message for the configured key.

If the table is append-only, all messages will have a true flag and must be interpreted as insertions.

Method Summary

Modifier and Type	Method and Description
default org.apache.flink.api.common.typeinfo.TypeInformation<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>>	getOutputType()
org.apache.flink.api.common.typeinfo.TypeInformation<T>	getRecordType() Returns the requested record type.
void	setIsAppendOnly(Boolean isAppendOnly) Specifies whether the Table to write is append-only or not.
void	setKeyFields(String[] keys) Configures the unique key fields of the Table to write.

Methods inherited from interface org.apache.flink.table.sinks.StreamTableSink

consumeDataStream, emitDataStream

Methods inherited from interface org.apache.flink.table.sinks.TableSink

configure, getConsumedDataType, getFieldNames, getFieldTypes, getTableSchema

Method Detail

setKeyFields

void setKeyFields(String[] keys)

Configures the unique key fields of the Table to write. The method is called after TableSink.configure(String[], TypeInformation[]).

The keys array might be empty, if the table consists of a single (updated) record. If the table does not have a key and is append-only, the keys attribute is null.

Parameters:

keys - the field names of the table's keys, an empty array if the table has a single row, and null if the table is append-only and has no key.

setIsAppendOnly

void setIsAppendOnly(Boolean isAppendOnly)

Specifies whether the Table to write is append-only or not.

Parameters:

isAppendOnly - true if the table is append-only, false otherwise.

getRecordType

org.apache.flink.api.common.typeinfo.TypeInformation<T> getRecordType()

Returns the requested record type.

getOutputType

default org.apache.flink.api.common.typeinfo.TypeInformation<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>> getOutputType()

Specified by:

getOutputType in interface org.apache.flink.table.sinks.TableSink<org.apache.flink.api.java.tuple.Tuple2<Boolean,T>>