Google BigQuery Storage v1 API - Class BigQueryReadClientImpl (3.16.0) 

public sealed class BigQueryReadClientImpl : BigQueryReadClient

Reference documentation and code samples for the Google BigQuery Storage v1 API class BigQueryReadClientImpl.

BigQueryRead client wrapper implementation, for convenient use.

Inheritance

object > BigQueryReadClient > BigQueryReadClientImpl

Namespace

Google.Cloud.BigQuery.Storage.V1

Assembly

Google.Cloud.BigQuery.Storage.V1.dll

Remarks

BigQuery Read API.

The Read API can be used to read data from BigQuery.

Constructors

BigQueryReadClientImpl(BigQueryReadClient, BigQueryReadSettings, ILogger)

public BigQueryReadClientImpl(BigQueryRead.BigQueryReadClient grpcClient, BigQueryReadSettings settings, ILogger logger)

Constructs a client wrapper for the BigQueryRead service, with the specified gRPC client and settings.

Parameters
Name Description
grpcClient BigQueryReadBigQueryReadClient

The underlying gRPC client.
settings BigQueryReadSettings

The base BigQueryReadSettings used within this client.
logger ILogger

Optional ILogger to use within this client.

Properties

GrpcClient

public override BigQueryRead.BigQueryReadClient GrpcClient { get; }

The underlying gRPC BigQueryRead client

Property Value
Type Description
BigQueryReadBigQueryReadClient
Overrides

Methods

CreateReadSession(CreateReadSessionRequest, CallSettings)

public override ReadSession CreateReadSession(CreateReadSessionRequest request, CallSettings callSettings = null)

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.

Parameters
Name Description
request CreateReadSessionRequest

The request object containing all of the parameters for the API call.
callSettings CallSettings

If not null, applies overrides to this RPC call.
Returns
Type Description
ReadSession

The RPC response.
Overrides

CreateReadSessionAsync(CreateReadSessionRequest, CallSettings)

public override Task<ReadSession> CreateReadSessionAsync(CreateReadSessionRequest request, CallSettings callSettings = null)

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.

Parameters
Name Description
request CreateReadSessionRequest

The request object containing all of the parameters for the API call.
callSettings CallSettings

If not null, applies overrides to this RPC call.
Returns
Type Description
TaskReadSession

A Task containing the RPC response.
Overrides

ReadRows(ReadRowsRequest, CallSettings)

public override BigQueryReadClient.ReadRowsStream ReadRows(ReadRowsRequest request, CallSettings callSettings = null)

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 100 MiB per response; read requests which attempt to read individual rows larger than 100 MiB will fail.

Each request also returns a set of stream statistics reflecting the current state of the stream.

Parameters
Name Description
request ReadRowsRequest

The request object containing all of the parameters for the API call.
callSettings CallSettings

If not null, applies overrides to this RPC call.
Returns
Type Description
BigQueryReadClientReadRowsStream

The server stream.
Overrides

SplitReadStream(SplitReadStreamRequest, CallSettings)

public override SplitReadStreamResponse SplitReadStream(SplitReadStreamRequest request, CallSettings callSettings = null)

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.

Parameters
Name Description
request SplitReadStreamRequest

The request object containing all of the parameters for the API call.
callSettings CallSettings

If not null, applies overrides to this RPC call.
Returns
Type Description
SplitReadStreamResponse

The RPC response.
Overrides

SplitReadStreamAsync(SplitReadStreamRequest, CallSettings)

public override Task<SplitReadStreamResponse> SplitReadStreamAsync(SplitReadStreamRequest request, CallSettings callSettings = null)

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.

Parameters
Name Description
request SplitReadStreamRequest

The request object containing all of the parameters for the API call.
callSettings CallSettings

If not null, applies overrides to this RPC call.
Returns
Type Description
TaskSplitReadStreamResponse

A Task containing the RPC response.
Overrides