--- title: Create Couchbase Transactions with SQL++ description: How to create Couchbase transactions using SQL++. pubDate: 2026-08-17T09:53:44.266Z antora: editUrl: https://github.com/couchbaselabs/docs-devex/edit/capella/modules/guides/pages/transactions.adoc xref: xref:cloud:guides:transactions.adoc[] --- [Consult the llms.txt file for a full list of contents](/llms.txt) [View original HTML](/cloud/guides/transactions.html) # Create Couchbase Transactions with SQL++ > How to create Couchbase transactions using SQL++. ## [](#introduction)Introduction Couchbase transactions enable you to carry out ACID (atomic, consistent, isolated, and durable) actions on the database. This how-to guide covers SQL++ support for Couchbase transactions. Some SDKs also support Couchbase transactions. For more information, see [Related Links](#related-links). Only DML (data modification language) statements are permitted within a transaction: [INSERT](../n1ql/n1ql-language-reference/insert.md), [UPSERT](../n1ql/n1ql-language-reference/upsert.md), [DELETE](../n1ql/n1ql-language-reference/delete.md), [UPDATE](../n1ql/n1ql-language-reference/update.md), [MERGE](../n1ql/n1ql-language-reference/merge.md), [SELECT](#n1ql:n1ql-language-reference/select.adoc), [EXECUTE FUNCTION](../n1ql/n1ql-language-reference/execfunction.md), [PREPARE](../n1ql/n1ql-language-reference/prepare.md), or [EXECUTE](../n1ql/n1ql-language-reference/execute.md). If you want to try out the examples in this section, follow the instructions given in [Create an Account and Deploy Your Free Tier Operational Cluster](../get-started/create-account.md) to create a free account, deploy a cluster, and load a sample dataset. To create a transaction using SQL++ in Couchbase Capella, you must use the [cbq shell](../n1ql/n1ql-intro/cbq.md). > [!WARNING] > Please note that the examples in this guide will alter the data in your sample database. To restore your sample data, remove and reinstall the travel sample data. Refer to [Import Data with the Capella UI](../clusters/data-service/import-data-documents.md) for details. ## [](#settings)Transaction Parameters You can specify various settings and parameters to control how transactions work. You can access transaction settings and parameters through the cbq shell. * CBQ Shell To specify parameters for a Couchbase transaction, use the `\SET` command. --- The following example shows transaction parameters for the examples on this page. ```sqlpp \SET -txtimeout "2m"; (1) \SET -scan_consistency "not_bounded"; (2) \SET -durability_level "none"; (3) ``` | **1** | The transaction timeout. | | ----- | ------------------------------------------------------------- | | **2** | The transaction scan consistency. | | **3** | Durability level of all the mutations within the transaction. | Click the View button to see this code in context. For more information, see [Transaction Settings and Parameters](../n1ql/n1ql-language-reference/transactions.md#settings-and-parameters). ## [](#single-statement)Single Statement Transactions You can create a Couchbase transaction containing a single DML statement. * CBQ Shell To execute a single statement as a transaction, set the `tximplicit` parameter to `true`. --- Context Set the query context to the `inventory` scope in the travel sample dataset. For more information, see [Setting the Query Context](select.md#query-context). Query ```sqlpp \SET -tximplicit true; UPDATE hotel SET price = "from £89" WHERE name = "Glasgow Grand Central"; ``` For more information, see [Query Tools](../n1ql/n1ql-language-reference/transactions.md#query-tools). ## [](#multiple-statement)Multiple Statement Transactions A Couchbase transaction may contain multiple DML statements. In this case, you must use SQL++ transaction statements to support the transaction: * [BEGIN TRANSACTION](#begin) to start the transaction. * [SET TRANSACTION](#set) to specify transaction settings. * [SAVEPOINT](#savepoint) to set a transaction savepoint. * [ROLLBACK TRANSACTION](#rollback) to roll back a transaction. * [COMMIT TRANSACTION](#commit) to commit a transaction. * CBQ Shell To execute a transaction containing multiple statements, create the transaction one statement at a time. Once you have started a transaction, all statements within the cbq shell session are assumed to be part of the same transaction until you rollback or commit the transaction. > [!NOTE] > You must be using cbq shell version 2.0 or above to use the automatic transaction ID functionality. --- For a worked example showing a complete transaction using SQL++, see [Transaction Worked Example](../n1ql/n1ql-language-reference/transactions.md#worked-example). Individual SQL++ transaction statements are described in the sections below. ### [](#begin)Begin a Transaction To start a transaction, use the `BEGIN TRANSACTION` statement. The following statement begins a transaction. ```sqlpp BEGIN TRANSACTION; ``` Click the View button to see this code in context. Result ```json { "nodeUUID": "9803422b02fd9e6c9e7156b8ddb2d840", "txid": "fab2bd20-322e-4ed0-bc4e-035db995f349" (1) } ``` | **1** | Beginning a transaction returns the transaction ID. | | ----- | --------------------------------------------------- | For more information, see [BEGIN TRANSACTION](../n1ql/n1ql-language-reference/begin-transaction.md). ### [](#set)Specify Transaction Settings To specify transaction settings, use the `SET TRANSACTION` statement. > [!NOTE] > Currently, the only available transaction setting is `ISOLATION LEVEL READ COMMITTED`. This setting is enabled by default. The `SET TRANSACTION` statement is therefore optional and may be omitted. The following statement specifies transaction settings. ```sqlpp SET TRANSACTION ISOLATION LEVEL READ COMMITTED; ``` Click the View button to see this code in context. For more information, see [SET TRANSACTION](../n1ql/n1ql-language-reference/set-transaction.md). ### [](#savepoint)Set a Savepoint To set a savepoint within a transaction, use the `SAVEPOINT` statement and specify a name for the savepoint. The following statement sets a savepoint. ```sqlpp SAVEPOINT s1; ``` Click the View button to see this code in context. For more information, see [SAVEPOINT](../n1ql/n1ql-language-reference/savepoint.md). ### [](#rollback)Roll Back a Transaction To roll back a transaction, use the `ROLLBACK TRANSACTION` statement. By default, this statement rolls back the entire transaction. If you want to roll back to a savepoint, use the `TO SAVEPOINT` keywords and specify the savepoint name. The following statement rolls back a transaction to a specified savepoint. ```sqlpp ROLLBACK TRANSACTION TO SAVEPOINT s2; ``` Click the View button to see this code in context. For more information, see [ROLLBACK TRANSACTION](../n1ql/n1ql-language-reference/rollback-transaction.md). ### [](#commit)Commit a Transaction To commit a transaction, use the `COMMIT TRANSACTION` statement. The following statement commits a transaction. ```sqlpp COMMIT TRANSACTION; ``` Click the View button to see this code in context. For more information, see [COMMIT TRANSACTION](../n1ql/n1ql-language-reference/commit-transaction.md). ## [](#related-links)Related Links Reference and explanation: * [Transactions](../../server/current/learn/data/transactions.md) * [SQL++ Support for Couchbase Transactions](../n1ql/n1ql-language-reference/transactions.md) Online transaction simulator: * [Query Transaction Simulator](https://transactions.couchbase.com) Transactions with SDKs: * C | [C++](../../cxx-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [.NET](../../dotnet-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [Go](../../go-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [Java](../../java-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [Kotlin](../../kotlin-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [Node.js](../../nodejs-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [PHP](../../php-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| [Python](../../python-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)| Ruby | Rust | [Scala](../../scala-sdk/current/howtos/distributed-acid-transactions-from-the-sdk.md)