Class SpannerTransaction

Represents a SQL transaction to be made in a Spanner database. A transaction in Cloud Spanner is a set of reads and writes that execute atomically at a single logical point in time across columns, rows, and tables in a database.

Inheritance

object

MarshalByRefObject

DbTransaction

SpannerTransactionBase

SpannerTransaction

Implements

IDbTransaction

IDisposable

IAsyncDisposable

Inherited Members

DbTransaction.Dispose()

DbTransaction.DisposeAsync()

DbTransaction.Connection

MarshalByRefObject.GetLifetimeService()

MarshalByRefObject.InitializeLifetimeService()

object.GetHashCode()

object.GetType()

object.ToString()

Namespace: Google.Cloud.Spanner.Data

Assembly: Google.Cloud.Spanner.Data.dll

Syntax

public sealed class SpannerTransaction : SpannerTransactionBase, IDbTransaction, IDisposable, IAsyncDisposable

Properties

CommitPriority

The RPC priority to use for the commit RPC of this transaction. This can only be set for read/write transactions. This priority is not used for commands that are executed on this transaction. Use Priority to set the priority of commands. The default priority is Unspecified.

Declaration

public Priority CommitPriority { get; set; }

Property Value

Type	Description
Priority

CommitTimeout

Gets or sets the wait time before terminating the attempt to Commit() or Rollback() and generating an error. Defaults to the timeout from the connection string. A value of '0' normally indicates that no timeout should be used (it waits an infinite amount of time). However, if you specify AllowImmediateTimeouts=true in the connection string, '0' will cause a timeout that expires immediately. This is normally used only for testing purposes.

Declaration

public int CommitTimeout { get; set; }

Property Value

Type	Description
int

DbConnection

Specifies the DbConnection object associated with the transaction.

Declaration

protected override DbConnection DbConnection { get; }

Property Value

Type	Description
DbConnection	The DbConnection object associated with the transaction.

Overrides

DbTransaction.DbConnection

DisposeBehavior

Specifies how resources are treated when Dispose(bool) is called. Defaults to Default. For a pooled transaction, Default will cause transactional resources to be sent back into a shared pool for re-use. For a detached transaction the default behaviour is to do nothing with transactional resources. If set to CloseResources all transactional resource will be closed. A detached transaction must have one process choose CloseResources to avoid leaks of transactional resources.

Declaration

public DisposeBehavior DisposeBehavior { get; set; }

Property Value

Type	Description
DisposeBehavior

IsDetached

Whether this transaction is detached or not. A detached transaction's resources are not pooled, so the transaction may be shared across processes for instance, for partitioned reads.

Declaration

public bool IsDetached { get; }

Property Value

Type	Description
bool

IsolationLevel

Specifies the IsolationLevel for this transaction.

Declaration

public override IsolationLevel IsolationLevel { get; }

Property Value

Type	Description
IsolationLevel	The IsolationLevel for this transaction.

Overrides

DbTransaction.IsolationLevel

LogCommitStats

Specifies whether this transaction should request commit statistics from the backend and log these. This property is by default equal to the value set on the SpannerConnection of this transaction, but can be overridden for a specific transaction.

Declaration

public bool LogCommitStats { get; set; }

Property Value

Type	Description
bool

MaxCommitDelay

The maximum amount of time the commit may be delayed server side for batching with other commits. The bigger the delay, the better the throughput (QPS), but at the expense of commit latency. If set to Zero, commit batching is disabled. May be null, in which case commits will continue to be batched as they had been before this configuration option was made available to Spanner API consumers. May be set to any value between Zero and 500ms.

Declaration

public TimeSpan? MaxCommitDelay { get; set; }

Property Value

Type	Description
TimeSpan?

Mode

Indicates the TransactionMode for the transaction.

Declaration

public TransactionMode Mode { get; }

Property Value

Type	Description
TransactionMode

Remarks

Cloud Spanner supports two transaction modes:

Locking read-write transactions are the only transaction type that support writing data into Cloud Spanner. These transactions rely on pessimistic locking and, if necessary, two-phase commit. Locking read-write transactions may abort, requiring the application to retry.
Read-only transactions provide guaranteed consistency across several reads, but do not allow writes. Read-only transactions can be configured to read at timestamps in the past. Read-only transactions do not need to be committed and do not take locks.

ReadTimestamp

The read timestamp of the read-only transaction if ReturnReadTimestamp is true, else null.

Declaration

public Timestamp ReadTimestamp { get; }

Property Value

Type	Description
Timestamp

Tag

The transaction tag to use for this transaction. This can only be set for read/write transactions, and must be set before any statements are executed on the transaction.

Declaration

public string Tag { get; set; }

Property Value

Type	Description
string

TimestampBound

Tells Cloud Spanner how to choose a timestamp at which to read the data for read-only transactions.

Declaration

public TimestampBound TimestampBound { get; }

Property Value

Type	Description
TimestampBound

Remarks

The types of timestamp bounds are:

Strong (the default): read the latest data.
Bounded staleness: read a version of the data that's no staler than a bound.
Exact staleness: read the version of the data at an exact timestamp.

TransactionId

Identifying information about this transaction.

Declaration

public TransactionId TransactionId { get; }

Property Value

Type	Description
TransactionId

Methods

Commit()

Commits the database transaction.

Declaration

public override void Commit()

Overrides

DbTransaction.Commit()

Commit(out DateTime)

Commits the database transaction synchronously, returning the database timestamp for the commit via timestamp.

Declaration

public void Commit(out DateTime timestamp)

Parameters

Type	Name	Description
DateTime	timestamp	Returns the UTC timestamp when the data was written to the database.

CommitAsync(CancellationToken)

Commits the database transaction asynchronously, returning the commit timestamp.

Declaration

public Task<DateTime> CommitAsync(CancellationToken cancellationToken = default)

Parameters

Type	Name	Description
CancellationToken	cancellationToken	A cancellation token used for this task.

Returns

Type	Description
Task<DateTime>	Returns the UTC timestamp when the data was written to the database.

CreateBatchDmlCommand()

Creates a new SpannerBatchCommand to execute batched DML statements within this transaction. You can add commands to the batch by using Add(SpannerCommand), Add(SpannerCommandTextBuilder, SpannerParameterCollection) and Add(string, SpannerParameterCollection).

Declaration

public SpannerBatchCommand CreateBatchDmlCommand()

Returns

Type	Description
SpannerBatchCommand

Dispose(bool)

Releases the unmanaged resources used by the DbTransaction and optionally releases the managed resources.

Declaration

protected override void Dispose(bool disposing)

Parameters

Type	Name	Description
bool	disposing	If true, this method releases all resources held by any managed objects that this DbTransaction references.

Overrides

DbTransaction.Dispose(bool)

Rollback()

Rolls back a transaction from a pending state.

Declaration

public override void Rollback()

Overrides

DbTransaction.Rollback()

RollbackAsync(CancellationToken)

Rolls back a transaction asynchronously.

Declaration

public override Task RollbackAsync(CancellationToken cancellationToken = default)

Parameters

Type	Name	Description
CancellationToken	cancellationToken	A cancellation token used for this task.

Returns

Type	Description
Task

Overrides

DbTransaction.RollbackAsync(CancellationToken)