public class PrepareWrite<T,DestinationT> extends PTransform<PCollection<T>,PCollection<KV<DestinationT,TableRow>>>
PCollection
for writing to BigQuery. Use the table function to determine
which tables each element is written to, and format the element into a TableRow
using the
user-supplied format function.name
Constructor and Description |
---|
PrepareWrite(DynamicDestinations<T,DestinationT> dynamicDestinations,
SerializableFunction<T,TableRow> formatFunction) |
Modifier and Type | Method and Description |
---|---|
PCollection<KV<DestinationT,TableRow>> |
expand(PCollection<T> input)
Applies this
PTransform on the given InputT , and returns its
Output . |
getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validate
public PrepareWrite(DynamicDestinations<T,DestinationT> dynamicDestinations, SerializableFunction<T,TableRow> formatFunction)
public PCollection<KV<DestinationT,TableRow>> expand(PCollection<T> input)
PTransform
PTransform
on the given InputT
, and returns its
Output
.
Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).
expand
in class PTransform<PCollection<T>,PCollection<KV<DestinationT,TableRow>>>