Class Transaction (7.5.0)

This type of transaction is the only way to write 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.

Calling either or signals that the transaction is finished and no further requests will be made. If for some reason you decide not to call one of the aformentioned methods, call to release the underlying Session.

Running a transaction via or automatically re-runs the transaction on ABORTED errors.

returns a plain Transaction object, requiring the user to retry manually.

Snapshot

Inheritance

Dml > Transaction

Package

@google-cloud/spanner

Examples


const {Spanner} = require('@google-cloud/spanner');
const spanner = new Spanner();

const instance = spanner.instance('my-instance');
const database = instance.database('my-database');

database.runTransaction(function(err, transaction) {
  // The `transaction` object is ready for use.
});

To manually control retrying the transaction, use the getTransaction method.


database.getTransaction(function(err, transaction) {
  // The `transaction` object is ready for use.
});

Constructors

(constructor)(session, options, queryOptions, requestOptions)

constructor(session: Session, options?: spannerClient.spanner.v1.TransactionOptions.ReadWrite, queryOptions?: IQueryOptions, requestOptions?: Pick<IRequestOptions, 'transactionTag'>);

Execute a DML statement and get the affected row count.

Transaction#runUpdate

Parameters
Name	Description
`session`	`Session`
`options`	`ReadWrite`
`queryOptions`	`IQueryOptions`
`requestOptions`	`Pick<IRequestOptions, 'transactionTag'>`

Example


const query = 'UPDATE Account SET Balance = 1000 WHERE Key = 1';

transaction.runUpdate(query, (err, rowCount) => {
  if (err) {
    // Error handling omitted.
  }
});

Properties

commitTimestamp

commitTimestamp?: PreciseDate;

commitTimestampProto

commitTimestampProto?: spannerClient.protobuf.ITimestamp;

Methods

batchUpdate(queries, options)

batchUpdate(queries: Array<string | Statement>, options?: BatchUpdateOptions | CallOptions): Promise<BatchUpdateResponse>;

Execute a series of DML statements and get the affected row counts.

If any of the DML statements fail, the returned error will contain a list of results for all successfully executed statements.

Parameters
Name	Description
`queries`	`Array<string \| Statement>`
`options`	`BatchUpdateOptions \| CallOptions` Options for configuring the request.

Returns

Type Description

Promise<BatchUpdateResponse>

{Promise

Examples


const queries = [
  {
    sql: 'INSERT INTO MyTable (Key, Value) VALUES (@key, @value)',
    params: {key: 'my-key', value: 'my-value'},
  },
  {
    sql: 'UPDATE MyTable t SET t.Value = @value WHERE t.KEY = @key',
    params: {key: 'my-other-key', value: 'my-other-value'}
  }
];

transaction.batchUpdate(queries, (err, rowCounts, apiResponse) => {
  if (err) {
    // Error handling omitted.
  }
});

If the callback is omitted, we'll return a Promise.


const [rowCounts, apiResponse] = await transaction.batchUpdate(queries);

batchUpdate(queries, callback)

batchUpdate(queries: Array<string | Statement>, callback: BatchUpdateCallback): void;

Parameters
Name	Description
`queries`	`Array<string \| Statement>`
`callback`	`BatchUpdateCallback`

Returns
Type	Description
`void`

batchUpdate(queries, options, callback)

batchUpdate(queries: Array<string | Statement>, options: BatchUpdateOptions | CallOptions, callback: BatchUpdateCallback): void;

Parameters
Name	Description
`queries`	`Array<string \| Statement>`
`options`	`BatchUpdateOptions \| CallOptions`
`callback`	`BatchUpdateCallback`

Returns
Type	Description
`void`

commit(options)

commit(options?: CommitOptions | CallOptions): Promise<CommitResponse>;

Commit the transaction.

Wrapper around .

Parameter
Name	Description
`options`	`CommitOptions \| CallOptions` Options for configuring the request.

Returns

Type Description

Promise<CommitResponse>

{Promise

Example


database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue a mutation (note that there is no callback passed to `insert`).
  transaction.insert('Singers', {
    SingerId: 'Id3b',
    Name: 'Joe West'
  });

  // Commit the transaction.
  transaction.commit(function(err, apiResponse) {
    if (!err) {
      // Get the commit timestamp on successful commits.
      const {commitTimestamp} = apiResponse;
    }
  });
});

commit(callback)

commit(callback: CommitCallback): void;

Parameter
Name	Description
`callback`	`CommitCallback`

Returns
Type	Description
`void`

commit(options, callback)

commit(options: CommitOptions | CallOptions, callback: CommitCallback): void;

Parameters
Name	Description
`options`	`CommitOptions \| CallOptions`
`callback`	`CommitCallback`

Returns
Type	Description
`void`

deleteRows(table, keys)

deleteRows(table: string, keys: Key[]): void;

Delete rows from a table.

Parameters
Name	Description
`table`	`string` The name of the table.
`keys`	`Key[]` The keys for the rows to delete. If using a composite key, provide an array within this array. See the example below.

Returns
Type	Description
`void`

Examples


const keys = ['Id1', 'Id2', 'Id3'];

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue this mutation until later calling `commit`.
  // Note that a callback is not passed to `deleteRows`.
  transaction.deleteRows('Singers', keys);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The rows were deleted successfully.
    }
  });
});

Provide an array for keys to delete rows with a composite key.


const keys = [
  [
    'Id1',
    'Name1'
  ],
  [
    'Id2',
    'Name2'
  ]
];

getUniqueKeys(rows)

static getUniqueKeys(rows: object[]): string[];

Takes a list of rows and returns all unique column names.

Parameter
Name	Description
`rows`	`object[]` The rows.

Returns
Type	Description
`string[]`	{string[]}

insert(table, rows)

insert(table: string, rows: object | object[]): void;

Insert rows of data into this table.

Parameters
Name	Description
`table`	`string` The name of the table.
`rows`	`object \| object[]` A map of names to values of data to insert into this table.

Returns
Type	Description
`void`

Examples


const row = {
  SingerId: 'Id3',
  Name: 'Eddie Wilson'
};

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue this mutation until later calling `commit`.
  // Note that a callback is not passed to `insert`.
  transaction.insert('Singers', row);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The row was inserted successfully.
    }
  });
});

Multiple rows can be inserted at once.


const row2 = {
  SingerId: 'Id3b',
  Name: 'Joe West'
};

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue multiple mutations until later calling `commit`.
  // Note that a callback is not passed to `insert`.
  transaction.insert('Singers', [
    row,
    row2
  ]);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The rows were inserted successfully.
    }
  });
});

replace(table, rows)

replace(table: string, rows: object | object[]): void;

Replace rows of data within a table.

Parameters
Name	Description
`table`	`string` The table to read from.
`rows`	`object \| object[]` A map of names to values of data to insert into this table.

Returns
Type	Description
`void`

Example


const row = {
  SingerId: 'Id3',
  Name: 'Joe West'
};

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue this mutation until later calling `commit`.
  // Note that a callback is not passed to `replace`.
  transaction.replace('Singers', row);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The row was replaced successfully.
    }
  });
});

rollback(gaxOptions)

rollback(gaxOptions?: CallOptions): Promise<void>;

Roll back a transaction, releasing any locks it holds. It is a good idea to call this for any transaction that includes one or more queries that you decide not to commit.

Wrapper around .

Parameter
Name	Description
`gaxOptions`	`CallOptions` Request configuration options, See CallOptions for more details.

Returns

Type Description

Promise<void>

{Promise

Example


database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  transaction.rollback(function(err) {
    if (!err) {
      // Transaction rolled back successfully.
    }
  });
});

rollback(callback)

rollback(callback: spannerClient.spanner.v1.Spanner.RollbackCallback): void;

Parameter
Name	Description
`callback`	`RollbackCallback`

Returns
Type	Description
`void`

rollback(gaxOptions, callback)

rollback(gaxOptions: CallOptions, callback: spannerClient.spanner.v1.Spanner.RollbackCallback): void;

Parameters
Name	Description
`gaxOptions`	`CallOptions`
`callback`	`RollbackCallback`

Returns
Type	Description
`void`

update(table, rows)

update(table: string, rows: object | object[]): void;

Update rows of data within a table.

Parameters
Name	Description
`table`	`string` The table to read from.
`rows`	`object \| object[]` A map of names to values of data to insert into this table.

Returns
Type	Description
`void`

Example


const row = {
  SingerId: 'Id3',
  Name: 'Joe West'
};

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue this mutation until later calling `commit`.
  // Note that a callback is not passed to `update`.
  transaction.update('Singers', row);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The row was updated successfully.
    }
  });
});

upsert(table, rows)

upsert(table: string, rows: object | object[]): void;

Insert or update rows of data within a table.

Parameters
Name	Description
`table`	`string` The table to read from.
`rows`	`object \| object[]` A map of names to values of data to insert into this table.

Returns
Type	Description
`void`

Example


const row = {
  SingerId: 'Id3',
  Name: 'Joe West'
};

database.runTransaction(function(err, transaction) {
  if (err) {
    // Error handling omitted.
  }

  // Queue this mutation until later calling `commit`.
  // Note that a callback is not passed to `upsert`.
  transaction.upsert('Singers', row);

  // Commit the transaction.
  transaction.commit(function(err) {
    if (!err) {
      // The row was updated or inserted successfully.
    }
  });
});

useInRunner()

useInRunner(): void;

Mark transaction as started from the runner.

Returns
Type	Description
`void`

useOptimisticLock()

useOptimisticLock(): void;

Use optimistic concurrency control for the transaction.

In this concurrency mode, operations during the execution phase, i.e., reads and queries, are performed without acquiring locks, and transactional consistency is ensured by running a validation process in the commit phase (when any needed locks are acquired). The validation process succeeds only if there are no conflicting committed transactions (that committed mutations to the read data at a commit timestamp after the read timestamp).

Returns
Type	Description
`void`