The representation of a Cloud Spanner transaction.
A transaction is a set of reads and writes that execute atomically at a single logical point in time across the columns/rows/tables in a database. Those reads and writes are grouped by passing them the same Transaction.
All reads/writes in the transaction must be executed within the same session, and that session may have only one transaction active at a time.
Spanner supports these transaction modes:
ReadOnly. Provides guaranteed consistency across several reads, but does not allow writes. Can be configured to read at timestamps in the past. Does not need to be committed and does not take locks.
ReadWrite. Supports reading and writing data at a single point in time. Uses pessimistic locking and, if necessary, two-phase commit. May abort, requiring the application to rerun.
SingleUse. A restricted form of a ReadOnly transaction where Spanner chooses the read timestamp.
Constructors
Transaction(ReadOnlyOptions)
Construction of read-only and read-write transactions.
Parameter
Name
Description
opts
ReadOnlyOptions
Transaction(ReadWriteOptions)
Construction of read-only and read-write transactions.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-22 UTC."],[[["\u003cp\u003eThis document outlines the \u003ccode\u003eTransaction\u003c/code\u003e class within the Google Cloud Spanner C++ client library, which facilitates the grouping of reads and writes into atomic operations.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eTransaction\u003c/code\u003e class supports three transaction modes: \u003ccode\u003eReadOnly\u003c/code\u003e, \u003ccode\u003eReadWrite\u003c/code\u003e, and \u003ccode\u003eSingleUse\u003c/code\u003e, each offering different capabilities and consistency guarantees.\u003c/p\u003e\n"],["\u003cp\u003eTransactions in Spanner operate within a single session, and only one transaction can be active in a session at any given time.\u003c/p\u003e\n"],["\u003cp\u003eCreating a \u003ccode\u003eTransaction\u003c/code\u003e object is a lazy operation, and no RPC calls are made until the first request to the server is executed, such as with an \u003ccode\u003eExecuteQuery()\u003c/code\u003e call.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eTransaction\u003c/code\u003e class functions as a regular value type, allowing for copy, assignment, and move operations.\u003c/p\u003e\n"]]],[],null,[]]
