Package org.apache.drill.exec.physical.resultSet.impl

Class PullResultSetReaderImpl

java.lang.Object
org.apache.drill.exec.physical.resultSet.impl.PullResultSetReaderImpl
All Implemented Interfaces:
PullResultSetReader
public class PullResultSetReaderImpl extends Object implements PullResultSetReader

Protocol

  1. Create an instance, passing in a PullResultSetReaderImpl.UpstreamSource to provide batches and optional selection vector.
  2. For each incoming batch:
    1. Call
      invalid reference 
      #start()
      to attach the batch. The associated BatchAccessor reports if the schema has changed.
    2. Call reader() to obtain a reader.
    3. Iterate over the batch using the reader.
    4. Call
      invalid reference 
      #release()
      to free the memory for the incoming batch. Or, to call
      invalid reference 
      #detach()
      to keep the batch memory.
  3. Call close() after all batches are read.