Google Cloud Spanner v1 API - Class ReadRequest (5.0.0-beta04)

public sealed class ReadRequest : IMessage<ReadRequest>, IEquatable<ReadRequest>, IDeepCloneable<ReadRequest>, IBufferMessage, IMessage

Reference documentation and code samples for the Google Cloud Spanner v1 API class ReadRequest.

The request for [Read][google.spanner.v1.Spanner.Read] and [StreamingRead][google.spanner.v1.Spanner.StreamingRead].

Inheritance

object > ReadRequest

Namespace

Google.Cloud.Spanner.V1

Assembly

Google.Cloud.Spanner.V1.dll

Constructors

ReadRequest()

public ReadRequest()

ReadRequest(ReadRequest)

public ReadRequest(ReadRequest other)
Parameter
Name Description
other ReadRequest

Properties

Columns

public RepeatedField<string> Columns { get; }

Required. The columns of [table][google.spanner.v1.ReadRequest.table] to be returned for each row matching this request.

Property Value
Type Description
RepeatedFieldstring

DataBoostEnabled

public bool DataBoostEnabled { get; set; }

If this is for a partitioned read and this field is set to true, the request is executed with Spanner Data Boost independent compute resources.

If the field is set to true but the request does not set partition_token, the API returns an INVALID_ARGUMENT error.

Property Value
Type Description
bool

DirectedReadOptions

public DirectedReadOptions DirectedReadOptions { get; set; }

Directed read options for this request.

Property Value
Type Description
DirectedReadOptions

Index

public string Index { get; set; }

If non-empty, the name of an index on [table][google.spanner.v1.ReadRequest.table]. This index is used instead of the table primary key when interpreting [key_set][google.spanner.v1.ReadRequest.key_set] and sorting result rows. See [key_set][google.spanner.v1.ReadRequest.key_set] for further information.

Property Value
Type Description
string

KeySet

public KeySet KeySet { get; set; }

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in [table][google.spanner.v1.ReadRequest.table] to be yielded, unless [index][google.spanner.v1.ReadRequest.index] is present. If [index][google.spanner.v1.ReadRequest.index] is present, then [key_set][google.spanner.v1.ReadRequest.key_set] instead names index keys in [index][google.spanner.v1.ReadRequest.index].

If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is empty, rows are yielded in table primary key order (if [index][google.spanner.v1.ReadRequest.index] is empty) or index key order (if [index][google.spanner.v1.ReadRequest.index] is non-empty). If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is not empty, rows will be yielded in an unspecified order.

It is not an error for the key_set to name rows that do not exist in the database. Read yields nothing for nonexistent rows.

Property Value
Type Description
KeySet

Limit

public long Limit { get; set; }

If greater than zero, only the first limit rows are yielded. If limit is zero, the default is no limit. A limit cannot be specified if partition_token is set.

Property Value
Type Description
long

LockHint

public ReadRequest.Types.LockHint LockHint { get; set; }

Optional. Lock Hint for the request, it can only be used with read-write transactions.

Property Value
Type Description
ReadRequestTypesLockHint

OrderBy

public ReadRequest.Types.OrderBy OrderBy { get; set; }

Optional. Order for the returned rows.

By default, Spanner will return result rows in primary key order except for PartitionRead requests. For applications that do not require rows to be returned in primary key (ORDER_BY_PRIMARY_KEY) order, setting ORDER_BY_NO_ORDER option allows Spanner to optimize row retrieval, resulting in lower latencies in certain cases (e.g. bulk point lookups).

Property Value
Type Description
ReadRequestTypesOrderBy

PartitionToken

public ByteString PartitionToken { get; set; }

If present, results will be restricted to the specified partition previously created using PartitionRead(). There must be an exact match for the values of fields common to this message and the PartitionReadRequest message used to create this partition_token.

Property Value
Type Description
ByteString

RequestOptions

public RequestOptions RequestOptions { get; set; }

Common options for this request.

Property Value
Type Description
RequestOptions

ResumeToken

public ByteString ResumeToken { get; set; }

If this request is resuming a previously interrupted read, resume_token should be copied from the last [PartialResultSet][google.spanner.v1.PartialResultSet] yielded before the interruption. Doing this enables the new read to resume where the last read left off. The rest of the request parameters must exactly match the request that yielded this token.

Property Value
Type Description
ByteString

Session

public string Session { get; set; }

Required. The session in which the read should be performed.

Property Value
Type Description
string

SessionAsSessionName

public SessionName SessionAsSessionName { get; set; }

SessionName-typed view over the Session resource name property.

Property Value
Type Description
SessionName

Table

public string Table { get; set; }

Required. The name of the table in the database to be read.

Property Value
Type Description
string

Transaction

public TransactionSelector Transaction { get; set; }

The transaction to use. If none is provided, the default is a temporary read-only transaction with strong concurrency.

Property Value
Type Description
TransactionSelector