Interface BigQueryReadGrpc.AsyncService

All Known Implementing Classes:
BigQueryReadGrpc.BigQueryReadImplBase
Enclosing class:
BigQueryReadGrpc

public static interface BigQueryReadGrpc.AsyncService
 BigQuery Read API.
 The Read API can be used to read data from BigQuery.
 
  • Method Details

    • createReadSession

      default void createReadSession(CreateReadSessionRequest request, io.grpc.stub.StreamObserver<ReadSession> responseObserver)
       Creates a new read session. A read session divides the contents of a
       BigQuery table into one or more streams, which can then be used to read
       data from the table. The read session also specifies properties of the
       data to be read, such as a list of columns or a push-down filter describing
       the rows to be returned.
       A particular row can be read by at most one stream. When the caller has
       reached the end of each stream in the session, then all the data in the
       table has been read.
       Data is assigned to each stream such that roughly the same number of
       rows can be read from each stream. Because the server-side unit for
       assigning data is collections of rows, the API does not guarantee that
       each stream will return the same number or rows. Additionally, the
       limits are enforced based on the number of pre-filtered rows, so some
       filters can lead to lopsided assignments.
       Read sessions automatically expire 6 hours after they are created and do
       not require manual clean-up by the caller.
       
    • readRows

      default void readRows(ReadRowsRequest request, io.grpc.stub.StreamObserver<ReadRowsResponse> responseObserver)
       Reads rows from the stream in the format prescribed by the ReadSession.
       Each response contains one or more table rows, up to a maximum of 128 MB
       per response; read requests which attempt to read individual rows larger
       than 128 MB will fail.
       Each request also returns a set of stream statistics reflecting the current
       state of the stream.
       
    • splitReadStream

      default void splitReadStream(SplitReadStreamRequest request, io.grpc.stub.StreamObserver<SplitReadStreamResponse> responseObserver)
       Splits a given `ReadStream` into two `ReadStream` objects. These
       `ReadStream` objects are referred to as the primary and the residual
       streams of the split. The original `ReadStream` can still be read from in
       the same manner as before. Both of the returned `ReadStream` objects can
       also be read from, and the rows returned by both child streams will be
       the same as the rows read from the original stream.
       Moreover, the two child streams will be allocated back-to-back in the
       original `ReadStream`. Concretely, it is guaranteed that for streams
       original, primary, and residual, that original[0-j] = primary[0-j] and
       original[j-n] = residual[0-m] once the streams have been read to
       completion.