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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-22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 levels of consistency and write capabilities.\u003c/p\u003e\n"],["\u003cp\u003eCreating a \u003ccode\u003eTransaction\u003c/code\u003e object is a lazy operation; the actual transaction creation on the server occurs during the first server request, such as \u003ccode\u003eExecuteQuery()\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eTransaction\u003c/code\u003e class is a regular value type and can be constructed using \u003ccode\u003eReadOnlyOptions\u003c/code\u003e or \u003ccode\u003eReadWriteOptions\u003c/code\u003e and also supports copy, assign, and move operations.\u003c/p\u003e\n"],["\u003cp\u003eThe document also contains an exhaustive list of the previous versions of the Spanner library, each link pointing to its respective documentation page.\u003c/p\u003e\n"]]],[],null,[]]
