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ROLLBACK TRANSACTION (Transact-SQL)

  • Artikkeli

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) Warehouse in Microsoft Fabric SQL database in Microsoft Fabric

This statement rolls back an explicit or implicit transaction to the beginning of the transaction, or to a savepoint inside the transaction. You can use ROLLBACK TRANSACTION to erase all data modifications made from the start of the transaction or to a savepoint. It also frees resources held by the transaction.

Rolling back a transaction doesn't include changes made to local variables or table variables. These changes aren't erased by this statement.

Transact-SQL syntax conventions

Syntax

Syntax for SQL Server and Azure SQL Database.

ROLLBACK { TRAN | TRANSACTION }
    [ transaction_name | @tran_name_variable
    | savepoint_name | @savepoint_variable ]
[ ; ]

Syntax for Synapse Data Warehouse in Microsoft Fabric, Azure Synapse Analytics, and Parallel Data Warehouse Database.

ROLLBACK { TRAN | TRANSACTION }
[ ; ]

Arguments

transaction_name

The name assigned to the transaction on BEGIN TRANSACTION. transaction_name must conform to the rules for identifiers, but only the first 32 characters of the transaction name are used. When you nest transactions, transaction_name must be the name from the outermost BEGIN TRANSACTION statement. transaction_name is always case-sensitive, even when the instance of SQL Server isn't case-sensitive.

@tran_name_variable

The name of a user-defined variable containing a valid transaction name. The variable must be declared with a char, varchar, nchar, or nvarchar data type.

savepoint_name

savepoint_name from a SAVE TRANSACTION statement. savepoint_name must conform to the rules for identifiers. Use savepoint_name when a conditional rollback should affect only part of the transaction.

@savepoint_variable

The name of a user-defined variable containing a valid savepoint name. The variable must be declared with a char, varchar, nchar, or nvarchar data type.

Error handling

A ROLLBACK TRANSACTION statement doesn't produce any messages to the user. If warnings are needed in stored procedures or triggers, use the RAISERROR or PRINT statements. RAISERROR is the preferred statement for indicating errors.

Remarks

ROLLBACK TRANSACTION without a savepoint_name or transaction_name rolls back to the beginning of the transaction. When you nest transactions, this same statement rolls back all inner transactions to the outermost BEGIN TRANSACTION statement. In both cases, ROLLBACK TRANSACTION decrements the @@TRANCOUNT system function to 0. ROLLBACK TRANSACTION <savepoint_name> doesn't decrement @@TRANCOUNT.

ROLLBACK TRANSACTION can't reference a savepoint_name in distributed transactions started either explicitly with BEGIN DISTRIBUTED TRANSACTION or escalated from a local transaction.

A transaction can't be rolled back after a COMMIT TRANSACTION statement is executed, except when the COMMIT TRANSACTION is associated with a nested transaction that is contained within the transaction being rolled back. In this instance, the nested transaction is rolled back, even if you issued a COMMIT TRANSACTION for it.

Within a transaction, duplicate savepoint names are allowed, but a ROLLBACK TRANSACTION using the duplicate savepoint name rolls back only to the most recent SAVE TRANSACTION using that savepoint name.

Interoperability

In stored procedures, ROLLBACK TRANSACTION statements without a savepoint_name or transaction_name roll back all statements to the outermost BEGIN TRANSACTION. A ROLLBACK TRANSACTION statement in a stored procedure that causes @@TRANCOUNT to have a different value when the stored procedure completes than the @@TRANCOUNT value when the stored procedure was called produces an informational message. This message doesn't affect subsequent processing.

If a ROLLBACK TRANSACTION is issued in a trigger:

  • All data modifications made to that point in the current transaction are rolled back, including any made by the trigger.

  • The trigger continues executing any remaining statements after the ROLLBACK statement. If any of these statements modify data, the modifications aren't rolled back. No nested triggers are fired by the execution of these remaining statements.

  • The statements in the batch after the statement that fired the trigger aren't executed.

@@TRANCOUNT is incremented by one when entering a trigger, even when in autocommit mode. (The system treats a trigger as an implied nested transaction.)

ROLLBACK TRANSACTION statements in stored procedures don't affect subsequent statements in the batch that called the procedure; subsequent statements in the batch are executed. ROLLBACK TRANSACTION statements in triggers terminate the batch containing the statement that fired the trigger; subsequent statements in the batch aren't executed.

The effect of a ROLLBACK on cursors is defined by these three rules:

  • With CURSOR_CLOSE_ON_COMMIT set ON, ROLLBACK closes, but doesn't deallocate all open cursors.

  • With CURSOR_CLOSE_ON_COMMIT set OFF, ROLLBACK doesn't affect any open synchronous STATIC or INSENSITIVE cursors or asynchronous STATIC cursors that were fully populated. Open cursors of any other type are closed but not deallocated.

  • An error that terminates a batch and generates an internal rollback deallocates all cursors that were declared in the batch containing the error statement. All cursors are deallocated regardless of their type or the setting of CURSOR_CLOSE_ON_COMMIT. This includes cursors declared in stored procedures called by the error batch. Cursors declared in a batch before the error batch are subject to the first two rules. A deadlock error is an example of this type of error. A ROLLBACK statement issued in a trigger also automatically generates this type of error.

Locking behavior

A ROLLBACK TRANSACTION statement specifying a savepoint_name releases any locks that are acquired beyond the savepoint, except for escalations and conversions. These locks aren't released, and they aren't converted back to their previous lock mode.

Permissions

Requires membership in the public role.

Examples

The following example shows the effect of rolling back a named transaction. After you create a table, the following statements start a named transaction, insert two rows, and then roll back the transaction named in the variable @TransactionName. Another statement outside of the named transaction inserts two rows. The query returns the results of the previous statements.

USE tempdb;
GO

CREATE TABLE ValueTable ([value] INT);
GO

DECLARE @TransactionName VARCHAR(20) = 'Transaction1';

BEGIN TRANSACTION @TransactionName

INSERT INTO ValueTable
VALUES (1), (2);

ROLLBACK TRANSACTION @TransactionName;

INSERT INTO ValueTable
VALUES (3), (4);

SELECT [value]
FROM ValueTable;

DROP TABLE ValueTable;

Here's the result set.

value
-----
3
4

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