@PublicEvolving public interface LookupTableSource extends DynamicTableSource
DynamicTableSourcethat looks up rows of an external storage system by one or more keys during runtime.
ScanTableSource, the source does not have to read the entire table and can
lazily fetch individual values from a (possibly continuously changing) external table when
Note: Compared to
LookupTableSource does only support
emitting insert-only changes currently (see also
RowKind). Further abilities are not
In the last step, the planner will call
obtaining a provider of runtime implementation. The key fields that are required to perform a
lookup are derived from a query by the planner and will be provided in the given
LookupTableSource.LookupContext.getKeys(). The values for those key fields are passed during runtime.
|Modifier and Type||Interface and Description|
Context for creating runtime implementation via a
Provides actual runtime implementation for reading the data.
|Modifier and Type||Method and Description|
Returns a provider of runtime implementation for reading the data.
LookupTableSource.LookupRuntimeProvider getLookupRuntimeProvider(LookupTableSource.LookupContext context)
There exist different interfaces for runtime implementation which is why
LookupTableSource.LookupRuntimeProvider serves as the base interface.
Independent of the provider interface, a source implementation can work on either
arbitrary objects or internal data structures (see
LookupTableSource.LookupContext offers utilities by the planner for creating runtime
implementation with minimal dependencies to internal data structures.
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