@PublicEvolving public interface DynamicTableSink
Dynamic tables are the core concept of Flink's Table & SQL API for processing both bounded and unbounded data in a unified fashion. By definition, a dynamic table can change over time.
When writing a dynamic table, the content can always be considered as a changelog (finite or
infinite) for which all changes are written out continuously until the changelog is exhausted.
The given ChangelogMode
indicates the set of changes that the sink accepts during
runtime.
For regular batch scenarios, the sink can solely accept insert-only rows and write out bounded streams.
For regular streaming scenarios, the sink can solely accept insert-only rows and can write out unbounded streams.
For change data capture (CDC) scenarios, the sink can write out bounded or unbounded streams
with insert, update, and delete rows. See also RowKind
.
Instances of DynamicTableSink
can be seen as factories that eventually produce
concrete runtime implementation for writing the actual data.
Depending on the optionally declared abilities, the planner might apply changes to an instance and thus mutate the produced runtime implementation.
A DynamicTableSink
can implement the following abilities:
In the last step, the planner will call getSinkRuntimeProvider(Context)
for obtaining
a provider of runtime implementation.
Modifier and Type | Interface and Description |
---|---|
static interface |
DynamicTableSink.Context
Context for creating runtime implementation via a
DynamicTableSink.SinkRuntimeProvider . |
static interface |
DynamicTableSink.DataStructureConverter
Converter for mapping between Flink's internal data structures and objects specified by the
given
DataType that can be passed into a runtime implementation. |
static interface |
DynamicTableSink.SinkRuntimeProvider
Provides actual runtime implementation for writing the data.
|
Modifier and Type | Method and Description |
---|---|
String |
asSummaryString()
Returns a string that summarizes this sink for printing to a console or log.
|
DynamicTableSink |
copy()
Creates a copy of this instance during planning.
|
ChangelogMode |
getChangelogMode(ChangelogMode requestedMode)
Returns the set of changes that the sink accepts during runtime.
|
DynamicTableSink.SinkRuntimeProvider |
getSinkRuntimeProvider(DynamicTableSink.Context context)
Returns a provider of runtime implementation for writing the data.
|
ChangelogMode getChangelogMode(ChangelogMode requestedMode)
The planner can make suggestions but the sink has the final decision what it requires. If
the planner does not support this mode, it will throw an error. For example, the sink can
return that it only supports ChangelogMode.insertOnly()
.
requestedMode
- expected set of changes by the current planDynamicTableSink.SinkRuntimeProvider getSinkRuntimeProvider(DynamicTableSink.Context context)
There might exist different interfaces for runtime implementation which is why DynamicTableSink.SinkRuntimeProvider
serves as the base interface. Concrete DynamicTableSink.SinkRuntimeProvider
interfaces might be located in other Flink modules.
Independent of the provider interface, the table runtime expects that a sink
implementation accepts internal data structures (see RowData
for more information).
The given DynamicTableSink.Context
offers utilities by the planner for creating runtime
implementation with minimal dependencies to internal data structures.
See org.apache.flink.table.connector.sink.SinkFunctionProvider
in flink-table-api-java-bridge
.
ParallelismProvider
DynamicTableSink copy()
String asSummaryString()
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