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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-22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 details the \u003ccode\u003eTransaction\u003c/code\u003e class within the Google Cloud Spanner C++ client library, covering its usage across multiple versions, from 2.11.0 to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eA \u003ccode\u003eTransaction\u003c/code\u003e in Spanner groups reads and writes to ensure they occur atomically, affecting data consistently across columns, rows, and tables in the database.\u003c/p\u003e\n"],["\u003cp\u003eSpanner supports three transaction modes: \u003ccode\u003eReadOnly\u003c/code\u003e (for consistent reads without writes), \u003ccode\u003eReadWrite\u003c/code\u003e (for both reads and writes), and \u003ccode\u003eSingleUse\u003c/code\u003e (a limited \u003ccode\u003eReadOnly\u003c/code\u003e mode where Spanner selects the read timestamp).\u003c/p\u003e\n"],["\u003cp\u003eCreating a \u003ccode\u003eTransaction\u003c/code\u003e object is a lazy operation; no immediate server calls are made, only when a request such as \u003ccode\u003eExecuteQuery()\u003c/code\u003e is made does it connect to the server.\u003c/p\u003e\n"],["\u003cp\u003eThe provided class features constructors and assignment operators that support read-only and read-write transactions, alongside standard copy, assign, and move semantics.\u003c/p\u003e\n"]]],[],null,[]]
