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sp_getbindtoken (Transact-SQL)

Applies to: SQL Server

Returns a unique identifier for the transaction. This unique identifier is a string used to bind sessions using sp_bindsession.

Important

This feature will be removed in a future version of SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. Use Multiple Active Results Sets (MARS) or distributed transactions instead. For more information, see Using Multiple Active Result Sets (MARS) in SQL Server Native Client.

Transact-SQL syntax conventions

Syntax

sp_getbindtoken [ @out_token = ] 'out_token' OUTPUT
[ ; ]

Arguments

[ @out_token = ] 'out_token'

The token to use to bind sessions. @out_token is varchar(255), with no default.

Return code values

None.

Result set

None.

Remarks

sp_getbindtoken returns a valid token only when the stored procedure is executed inside an active transaction. Otherwise, the Database Engine returns an error message. For example:

-- Declare a variable to hold the bind token.
-- No active transaction.
DECLARE @bind_token varchar(255);

-- Trying to get the bind token returns an error 3921.
EXECUTE sp_getbindtoken @bind_token OUTPUT;

Here's the result set.

Server: Msg 3921, Level 16, State 1, Procedure sp_getbindtoken, Line 4
Cannot get a transaction token if there is no transaction active.
Reissue the statement after a transaction has been started.

When sp_getbindtoken is used to enlist a distributed transaction connection inside an open transaction, SQL Server returns the same token. For example:

USE AdventureWorks2022;
GO

DECLARE @bind_token VARCHAR(255);
BEGIN TRANSACTION;
EXECUTE sp_getbindtoken @bind_token OUTPUT;
SELECT @bind_token AS Token1;
BEGIN DISTRIBUTED TRANSACTION;
EXECUTE sp_getbindtoken @bind_token OUTPUT;
SELECT @bind_token AS Token2;
--COMMIT TRANSACTION;
--COMMIT TRANSACTION;

Both SELECT statements return the same token:

Token1
------
PKb'gN5<9aGEedk_16>8U=5---/5G=--

Token2
------
PKb'gN5<9aGEedk_16>8U=5---/5G=--

The bind token can be used with sp_bindsession to bind new sessions to the same transaction. The bind token is only valid locally inside each instance of the Database Engine and can't be shared across multiple instances.

To obtain and pass a bind token, you must run sp_getbindtoken before executing sp_bindsession for sharing the same lock space. If you obtain a bind token, sp_bindsession runs correctly.

Note

We recommend that you use the srv_getbindtoken Open Data Services application programming interface (API) to obtain a bind token to be used from an extended stored procedure.

Permissions

Requires membership in the public role.

Examples

The following example obtains a bind token and displays the bind token name.

DECLARE @bind_token VARCHAR(255);
BEGIN TRANSACTION;
EXECUTE sp_getbindtoken @bind_token OUTPUT;
SELECT @bind_token AS Token;
--COMMIT TRANSACTION;

Here's the result set.

Token
-----
\0]---5^PJK51bP<1F<-7U-]ANZ